The Best-Kept Secret on Each MLB Roster Entering 2020 Season

Until the league and the union can figure out a way to safely and fairly get back to work, the 2020 Major League Baseball season is strictly theoretical.

But if it does eventually become a reality, expanded rosters and an abbreviated schedule will require all hands to be on deck. In an environment such as this, unsung heroes could become regular heroes in a hurry.

With this in mind, we went looking for every team's biggest secret weapon. These are guys whose names don't leap off the page, yet they have the goods to leave their mark on the 2020 season.

We'll proceed in alphabetical order by city.

The Arizona Diamondbacks will need better relief pitching in 2020 than what they got last season, in which their bullpen posted a 4.26 ERA with the National League's second-lowest strikeout rate.

To his credit, though, Kevin Ginkel did his part to right the ship after he arrived in August.

In 25 appearances, the 26-year-old racked up a 1.48 ERA with 28 strikeouts in 24.1 innings. He also posted the lowest xwOBA—which is based on strikeouts, walks and contact quality—out of all Arizona pitchers who faced at least 50 batters.

Though D-backs manager Torey Lovullo will have to be mindful of Ginkel's platoon split, he might nonetheless arise as a go-to setup man for closer Archie Bradley.

Chris Martin might like to have a mulligan on the first impression he made as an Atlanta Brave in 2019.

After coming over in a deadline-day trade with the Texas Rangers, he made 20 appearances with Atlanta and pitched to a modest 4.08 ERA.

Yet the Braves re-signed Martin to a two-year, $14 million deal anyway. They were surely enthused by his ability to throw strikes, as his 13.0 strikeout-to-walk ratio was by far the highest of any pitcher who made over 50 appearances in 2019.

Any more of that in 2020 should help Martin's ERA come down, potentially earning him more high-leverage innings alongside the late-inning tandem of Mark Melancon and Will Smith.

Because they have one of the most anonymous rosters in baseball, the Baltimore Orioles are arguably nothing but secret weapons.

Out of the bunch, Austin Hays is actually worth being excited about.

The 24-year-old broke out as a top prospect in 2017 when he posted a .958 OPS and 32 home runs in the minors. But he didn't do much with his cup of coffee with the Orioles in September, and he was sidetracked by injuries in 2018 and 2019.

Last September, however, Hays showed Baltimore something with a .947 OPS over 21 games in the majors. A small sample size, to be sure, but his excellent xwOBA provides one reason to believe in it as a springboard to stardom.

The Boston Red Sox no longer bear much resemblance to the club that won the World Series in 2018, yet 2020 might at least be a good season for developing talent.

To this end, Darwinzon Hernandez got a head start in 2019.

In the wake of his mixed results as a starter, the Red Sox put Hernandez in their bullpen July 16 last season. Despite a 4.32 ERA and 20 walks, he struck out 46 batters in 25 innings the rest of the way.

At an average of 95.7 mph, Hernandez's fastball was one of the hardest thrown by a left-hander after July 15. If he learns to control it better, he might become the American League's answer to Josh Hader.

The Chicago Cubs bullpen wasn't particularly good in 2019, and it promptly lost several core pieces to free agency.

The Cubs did, however, pick up an intriguing right-hander when they acquired Casey Sadler in January.

After doing a little of this and a little of that over many years in the Pittsburgh Pirates system, Sadler found something in 2019. He achieved a career-high strikeout rate at Triple-A and put up a 2.33 ERA in 24 appearances for the Los Angeles Dodgers.

With a hard sinker and sharp curveball at his disposal, the 29-year-old could pitch his way into late-inning duty in his first season with Chicago.

Though their lineup is otherwise loaded with stars, the Chicago White Sox don't have a clear answer at second base.

Ideally, top prospect Nick Madrigal will claim the position at some point in 2020. But if he can't, Danny Mendick might take it.

Given that he was initially undrafted out of high school, it's a small miracle that Mendick made it to the majors last season. Albeit in only 16 games, he also showed well with a .308 average.

Granted, the 26-year-old also struck out 11 times in only 39 at-bats. But if he can reclaim the solid plate discipline he showed in the minors, he might become a solid regular who does a little bit of everything.

Whenever this season opens up, the Cincinnati Reds will arguably be the de facto favorites to win the National League Central.

They still have the starting rotation that was outstanding throughout 2019, and their offense now has a new look after the signings of Nicholas Castellanos, Mike Moustakas and Shogo Akiyama.

Plus, the Reds have a sneaky-good bullpen that will be even better if Robert Stephenson takes the next step after breaking out with a 3.76 ERA and 11.3 strikeouts per nine innings in 2019.

Though the 27-year-old averaged 95.0 mph on his fastball, his slider is his real moneymaker. It's a nasty pitch that only Justin Verlander and Max Scherzer topped in xwOBA.

It's doubtful that many people will favor the Cleveland Indians over the Minnesota Twins in the American League Central race, but nobody should rule the Tribe out altogether.

They've won at least 91 games in each of the last four seasons, and they're going into 2020 with a handful of star hurlers and an underrated offense.

The most unheralded piece of said offense is Jordan Luplow. After Cleveland acquired him from the Pittsburgh Pirates in 2018, he broke out with a .923 OPS and 15 homers in 85 games last season.

Though Luplow did almost all of his damage against left-handers, that's not necessarily a problem. He'll get plenty of at-bats as a platoon hitter and, thanks to the new three-batter minimum, as a pinch-hitter.

Between their lack of activity and all the Nolan Arenado trade rumors, the Colorado Rockies weren't exactly in a happy place when spring training opened up.

Still, they might have a chance to surprise some people this year. They would just need a few bounce-back performances and breakouts, including from Sam Hilliard.

As it is, Hilliard enjoyed an abbreviated breakthrough at the end of the 2019 season, posting a 1.006 OPS with seven home runs in 27 games with the Rockies.

Going forward, Hilliard must conquer the swing-and-miss weakness that's plagued him throughout his professional career. If he can manage that, his power and speed could make him a star.

No team was harder to watch in 2019 than the Detroit Tigers. They lost 114 games and gave up 333 more runs than they scored.

If nothing else, the Tigers can't possibly lose as many games in 2020. There could also be a few more bright spots along the way, up to and including JaCoby Jones.

To be sure, the 28-year-old didn't have a good season in 2019. Yet his .740 OPS was a career high, and he potentially deserved better. He also fielded his position well despite his slow jumps at the crack of the bat.

The general picture is that of a guy who's slowly getting it and who might soon click if he can figure out the finer points of his game.

Offensively, the Houston Astros still mostly resemble the juggernaut that they were last season. But without Gerrit Cole and Wade Miley, their pitching staff is another story.

The task of picking up the slack behind Justin Verlander and Zack Greinke will initially fall to Lance McCullers Jr., Jose Urquidy and Josh James. Of the three, don't underestimate Urquidy.

The 25-year-old has already shown some promise with the Astros, including in five scoreless innings in Game 4 of last year's World Series. Notably, he had a good changeup working in that game.

Because Urquidy also boasts a good fastball, curveball and slider, there's not much holding him back from stardom.

As they wait for their best prospects to arrive, the best thing the Kansas City Royals can do in the interim is dig up some surprise gems.

They tried to do this with Ryan O'Hearn last season, but it didn't work out. He mustered only a .650 OPS and 14 home runs in 105 games.

This is an opening for Ryan McBroom to wrest first base from O'Hearn. He didn't do much in a late-season cameo with the Royals in 2019, but before it came a .976 OPS and 26 homers in the New York Yankees system.

Because McBroom dramatically improved his walk-to-strikeout ratio, he clearly found something that had been missing before last season.

Whether they can take back the AL West is debatable, but the Los Angeles Angels are in for a different kind of season in 2020.

From Anthony Rendon to Julio Teheran to Dylan Bundy, they have some new pieces. Given his reputation, new manager Joe Maddon will surely use everything he has to work with.

Nobody should be more ready to play an active role than David Fletcher, who Maddon reportedly plans to use as his new Ben Zobrist. That is, a super-utility player who won't specialize in any one position.

Fletcher has the defensive chops for it, and he also holds the distinction of being the majors' best pure contact hitter. If he can muster a little more power, he'll play the Zobrist role perfectly.

The Los Angeles Dodgers had the most prolific offense in the National League last season, yet it figures to be even better in 2020.

That's largely a credit to dual MVPs Cody Bellinger and Mookie Betts, but the sheer depth of Los Angeles' offense is unmatched elsewhere in the Senior Circuit. And if there's an overlooked member of it, it's Matt Beaty.

At first glance, Beaty's performance as a rookie in 2019 might not look that impressive. He played in 99 games and put up a good but not great .775 OPS.

Against right-handers, however, Beaty had an .840 OPS with all but one of his 29 extra-base hits. As a sophomore, he can build on that while also potentially adding some new positions to his defensive portfolio.

Contrary to the Dodgers, the Miami Marlins had the least prolific offense in the National League a year ago.

However, more runs should be in store for 2020 after the club added Corey Dickerson, Jonathan Villar and Jesus Aguilar. They should also get a spark off the bench from Jon Berti.

The 30-year-old looked vaguely like a late bloomer last year, as he played well at Triple-A before hitting .273 while playing all over the field in 73 games with Miami.

In his sprint speed, Berti has at least one elite tool to fall back on. He could also benefit from more frequent at-bats against lefties, against whom he had an .883 OPS in 2019.

Apart from budding ace Brandon Woodruff, the Milwaukee Brewers had a tough time with their starting rotation in 2019.

The club's rotation now has a different look by way of three newcomers after Woodruff and Adrian Houser, the most intriguing of whom is 32-year-old Josh Lindblom.

Lindblom bounced around in the majors from 2011 to 2017, mostly working as a good but not great relief pitcher. He then went to Korea, where his sub-3.00 ERAs in 2018 and 2019 helped earned him a three-year deal with Milwaukee.

As noted by Steve Adams of MLB Trade Rumors, Lindblom boasts standout spin rates and a new pitch mix that emphasizes his fastball, splitter and cutter. These things could pave his way to a breakout.

The Minnesota Twins could use more consistent pitching in 2020 than they got in 2019, whether it's from their rotation or their bullpen.

For the latter, keep an eye out for Cody Stashak as a potential difference-maker.

His initial transition from starting to relieving in 2018 went well, and he built on it in 2019. He had a 3.21 ERA and an 8.2 strikeout-to-walk ratio in the minors. He then made 18 appearances for the Twins, yielding a 3.24 ERA with 25 strikeouts and only one walk.

Though Stashak's low-90s heater is vulnerable, his sharp control and hard-biting slider could be enough to get him into more high-leverage situations this year.

It's remarkable that the New York Mets won 86 games in 2019 despite their bullpen's efforts to ruin everything.

Mets relievers had a 4.99 ERA overall, in part because Edwin Diaz, Jeurys Familia and Robert Gsellman all put forth disappointing seasons. Each of the three must be better in 2020.

On the plus side, newcomer Dellin Betances should help right the ship if he stays healthy. And don't underestimate Brad Brach, who's back with the Mets after posting a 3.68 ERA for them late in 2019.

Though the former All-Star rekindled his fastball velocity, his rebirth had more to do with his suddenly breaking out a filthy cutter. The more he shows it off in 2020, the more he stands to help the Mets.

Next to guys like Aaron Judge, Giancarlo Stanton, Gary Sanchez and Gleyber Torres, Mike Ford doesn't stand out as a brand-name New York Yankees slugger.

But after the season he had in 2019, he should be sold short of nothing.

Ford began last year with a huge breakout at Triple-A, where he had a 1.007 OPS and 23 homers in 79 games. He carried it over to the majors, posting a .909 OPS with 12 homers in 50 games with New York.

Given that Ford posted the same xwOBA as Luke Voit, the latter might not want to assume that he can't lose his job at first base.

Though the Oakland Athletics didn't have much star power in their rotation or their bullpen in 2019, they finished the year with a solid 3.97 ERA.

That's in part because of Bob Melvin's deft managing and in part because there were some hidden gems in Oakland's mound staff. One of them was J.B. Wendelken.

Despite being limited to 27 appearances, the 27-year-old made an impression with a 3.58 ERA and only 21 hits and nine walks allowed in 32.2 innings. Moreover, only All-Star closer Liam Hendriks had a lower xwOBA.

That gets at the nastiness of Wendelken's stuff, as he throws in the mid-90s with gnarly movement on his curveball. Clearly, he's a shutdown setup man in the making.

The Philadelphia Phillies should hit well enough in 2020. The bigger question is how their pitching will fare.

Much will depend on whether incumbents Aaron Nola and Jake Arrieta and newcomer Zack Wheeler can carry their rotation, and whether closer Hector Neris gets enough support in the bullpen.

On the latter front, don't mistake Nick Pivetta for a non-factor. While he posted a modest 4.38 ERA after transitioning to the pen in 2019, hidden underneath that were some encouraging numbers.

To wit, Pivetta complemented his movement-rich curveball with a 95.7 mph fastball and struck out 31 batters in 24.2 innings. That performance could point his way to regular late-inning duty.

After cleaning house in response to a 93-loss season in 2019, the Pittsburgh Pirates must now hope to avoid the NL Central cellar in 2020.

To be frank, that's probably not happening. Yet the Pirates might not be altogether moribund, as they have a few treasures in their midst.

Consider Chris Stratton. The Pirates picked him up last May after he bombed with the Angels, and he promptly put himself together again with a 3.66 ERA in 28 appearances that spanned 46.2 innings.

Naturally, Stratton's move from starting to relieving boosted his average fastball from 90.8 mph to 93.0 mph. Between that and how well he spins his breaking stuff, he has it in him to become a relief ace.

In their bullpen, the San Diego Padres have an All-Star closer in Kirby Yates and a $34 million setup man in Drew Pomeranz.

Their best reliever, however, is arguably Emilio Pagan.

The Padres added Pagan in a trade that sent center fielder Manuel Margot to the Tampa Bay Rays in February. On their own, the 2.31 ERA and 7.4 strikeout-to-walk ratio he posted in 2019 are reason enough to believe San Diego's bullpen gained a game-changer.

Yet Pagan might have underachieved last season. His .221 xwOBA was the lowest of any pitcher who faced at least 100 batters. Any more of that, and he can become a superstar reliever.

Without longtime manager Bruce Bochy and ace Madison Bumgarner, the San Francisco Giants are staring down their first true rebuilding season in quite some time.

They'll still be worth watching, though, because you never know when you might catch a glimpse of Tyler Rogers.

The 29-year-old is fun to watch on account of his Chad Bradford-ian submarine throwing motion. The Giants also have big plans for him, as new manager Gabe Kapler has hinted at occasionally using him as an opener.

And why not? Rogers posted a 1.02 ERA in his first taste of the majors last September, and he's capable of getting both righties and lefties out with his sinker/curveball combination.

Despite the shockingly optimistic simulation of their 2020 season at Baseball Reference, the Seattle Mariners are likely in for a rough one in the real world.

Still, they might have some silver linings. Provided he makes a strong recovery from a torn ACL, one of them will be in the bullpen in the person of Austin Adams.

The Mariners acquired Adams from the Washington Nationals last May, after which he made 29 appearances and struck out 51 of the 124 batters he faced.

Adams posted the xwOBA to match, and it was mostly thanks to his liberal use of his tight slider. Any more of that, and he could pitch his way into closing duty.

The St. Louis Cardinals will need more offense in 2020 than they got in 2019, wherein they scored a below-average 4.7 runs per game.

Though veteran sluggers Paul Goldschmidt and Matt Carpenter bear the bulk of the responsibility for making better things happen this year, the Cardinals will also need a lift from their assorted youngsters.

Among this bunch, Rangel Ravelo looms as a potential X-factor in the club's outfield mix. He's done no worse than an .856 OPS in his last three seasons at Triple-A, where he specialized in crushing left-handers.

Though Ravelo didn't make an impact in his 29 games with the Cardinals last season, he hit the ball hard enough to earn a .351 xwOBA. For comparison, Goldschmidt finished at .361.

How the Tampa Bay Rays won 96 games in 2019 comes down to how well Kevin Cash managed the team through injuries to aces Blake Snell and Tyler Glasnow.

Cash won't have to work as hard in 2020 if those two stay healthy, yet he surely won't neglect the other interesting arms at his disposal. One of the more underrated ones belongs to Colin Poche.

The 26-year-old wasn't untouchable last year, as he served up nine home runs and a 4.70 ERA in 51.2 innings. However, he also used his electric fastball to strike out 72 batters, all while avoiding a platoon split.

Per his excellent .261 xwOBA from 2019, Poche might indeed get better results with it in 2020 even if he does the same thing all over again.

If all goes well, the Texas Rangers will get so much from their starting rotation in 2020 that their offense will merely need to keep up.

That proposition hinges on many things, including at least one wild card ticketed for the Rangers bench: Adolis Garcia.

The Rangers acquired Garcia last December following three modest seasons in the Cardinals organization. He most recently hit 32 home runs at Triple-A in 2019, but with only a .301 on-base percentage.

There's little question, however, that Garcia's power, speed and throwing arm are worthy of stardom. If the Rangers can get him to sharpen his plate approach, he might achieve it in 2020.

Even if the Toronto Blue Jays' young offense and rebuilt rotation do their part, their bullpen could keep them from returning to contention in 2020.

Ken Giles is one of MLB's best closers, but underneath him is a motley crew of setup men. Arguably the only one who carries any real intrigue is Rafael Dolis.

After flaming out in the majors in 2013, the 32-year-old found his footing in Japan. Over the last three seasons, he had a 2.67 ERA with 195 strikeouts in 175 innings.

Dolis found success by pairing his mid-90s heater with a new splitter. If that combo works in the majors as well as it did in Japan, he has eighth-inning duty in his near future.

Save for the notable absence of Anthony Rendon, the Washington Nationals mostly look like the same club that won the World Series in 2019.

Because of this, it isn't so easy to dig up secrets on their roster. Yet we'll make a case for Joe Ross.

The 27-year-old looked like a rising star as he was putting up a 3.52 ERA across the 2015 and 2016 seasons. But over the last three years, he's battled injuries and posted a 5.21 ERA when he's been healthy.

But in the nine starts he made in 2019, Ross teased by way of a 3.02 ERA that he still has it. If he indeed does, he'll take some pressure off Max Scherzer, Stephen Strasburg and Patrick Corbin this season.

Stats courtesy of Baseball Reference, FanGraphs and Baseball Savant.