Fluke or for Real? Breaking Down the Most Stunning MLB Starts to New Season

Nam Y. Huh/Associated Press

The old adage goes something like, "Baseball is a marathon, not a sprint." 

Indeed, a 162-game season ensures players will go through peaks and valleys, slumps and hitting streaks. Finishing strong is more important for both players and teams; just ask anyone on the 2019 Washington Nationals. 

That said, fast starts can precede stardom. Conversely, some players never quite recover from sluggish beginnings. How should these performances be rated, and how might early success—or lack thereof—project down the line?

Let's take a look at some of the most stunning starts to the 2021 season. The list will focus explicitly on players and will include those who have produced well beyond general expectation. It will also include a few whose campaigns have been more woeful.

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Yermin Mercedes has been in professional baseball since 2011. He did not get his first MLB at-bat until 2020, which was his lone at-bat of the season. But Mercedes has filled a massive void in the South Siders' lineup after Eloy Jimenez was lost to a torn pectoral. 

The 28-year-old made an enormous impact in his first two games, hitting safely in each of his first eight at-bats and racking up six RBI and three extra-base hits. He would run his hitting streak to six games and provide more fireworks with a 485-foot homer of Kansas City Royals starter Brad Keller on Thursday.

Mercedes' success (.556/.571/.889) is hard to pin down. On the one hand, he ranks in just the 22nd percentile in average exit velocity and 27th percentile in hard-hit rate. Mercedes also ranks in just the 22d percentile in chase rate. 

Judging off batted-ball numbers alone, it would seem regression is likely. But it isn't that simple. Mercedes ranks in the 94th percentile in max exit velocity and 84th percentile in barrel rate. He can give it a ride and consistently gets the barrel through.

The other important consideration is Mercedes was a .302/.366/.491 career hitter in the minors. He also ranks in the 91st percentile in whiff rate, which is suggestive of his hit tool. 

The numbers are unsustainable, but he has hit all along the way and only seems to be getting more comfortable at the dish. Mercedes could be an impact bat for the White Sox.

Bryan Woolston/Associated Press

Tyler Naquin never quite lived up to the promise he showed in his rookie season in Cleveland. But he sure is off to a fantastic start in Cincinnati.

Naquin has already surpassed his 2020 total with five homers through his first seven games. He has nearly as many walks (4) as he did in 40 games last year (5). The resulting slash line of .318/.444/1.000 has helped power a Reds offense that has also seen prolific performances from Nick Castellanos and Jonathan India, among others. 

Nothing about Naquin's start has been fluky. He ranks atop MLB in both average exit velocity and hard-hit rate. He also ranks in the 99th percentile in barrel rate and 95th percentile in max exit velocity.

Is this the year the 29-year-old really breaks out? Naquin's .632 OPS in 2020 might be slightly deceptive given he ranked in the 87th percentile in average exit velocity and 93rd percentile in hard-hit rate. The fact that he has maintained strong batted-ball numbers early is quite encouraging, especially now that he is playing in a more hitter-friendly environment at Great American Ball Park. 

The concern with Naquin is the swing-and-miss tendencies. He ranks in the 14th percentile in whiff rate, which doesn't bode all that well for how he'll fare once pitchers start making adjustments. It will also be interesting to see whether Jesse Winker digs into his playing time.

Still, Naquin could be a necessary run-producer with even greater upside if he can continue to draw walks and gets enough at-bats.

Kathy Willens/Associated Press

The Baltimore Orioles had a surprise in store when they swept the Boston Red Sox in their opening series. Outfielder Cedric Mullins was red-hot against Boston. 

Mullins racked up nine hits in three games, including a five-hit, three-double performance in the series finale. He epitomized the notion of creating steady traffic on the bases, consistently giving teammates the opportunity to drive in runs.

The 2015 13th-round pick has since cooled just a touch. But Mullins hit safely in each of his next four games, also clubbing a home run in an extra-innings win over the New York Yankees on April 7. He then had two more hits against the Boston Red Sox on Saturday.

Mullins will not be a big power guy. But he projects quite well as a line-drive hitter who can put the ball through the middle of the field. The 26-year-old has a 40.9 percent line-drive rate and ranks in the 70th percentile in average exit velocity.

It should be noted Mullins ranked below the 50th percentile in average exit velocity and was in just the 18th percentile in hard-hit rate in 2020. He also had a ground-ball rate over 50 percent in each of his first three seasons. 

Regression seems likely. However, it is an inherently good sign Mullins' line-drive percentage is so high considering he makes a good deal of contact.

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Pick your poison when it comes to Atlanta Braves hitters who have had a rough go of it early on. Freddie Freeman and Marcell Ozuna are scuffling, as is rookie outfielder Cristian Pache. 

However, second baseman Ozzie Albies' numbers have been the most shocking. Albies is slashing .111/.143/.148 and was hitless until the fifth game of the season. But the former Silver Slugger is bound to turn things around. 

Albies has just a .130 batting average on balls in play (BABIP). That is totally unsustainable, especially considering Albies is not pounding the ball into the ground and has a 21.7 percent line drive rate. 

Indeed, the 24-year-old ranks in the 77th percentile in expected batting average (xBA). He also has an 89.9 mph average exit velocity, which is his highest mark, albeit in a small sample size.

Albies' luck should start to turn, especially because he makes a lot of contact and is hitting the ball harder than in prior seasons.

Aaron Gash/Associated Press

Perhaps this is the Byron Buxton the Minnesota Twins were envisioning when they selected him with the second overall pick in 2012. 

Buxton has shown glimpses of his slugging capacity in each of the past two seasons. He slugged .513 in 2019 and hit 13 homers in just 39 games in 2020. But his mammoth start to this season feels a bit different.

The 27-year-old is slashing .421/.476/1.211 with four homers and three doubles. He leads MLB in OPS (1.687) and has a 362 OPS+. He's also displayed feats of exceptional power.

Buxton ranks in the 96th percentile or higher in all of hard-hit rate, barrel percentage, average exit velocity and max exit velocity. He has clubbed everything in sight, whether it's been a slow slider out over the middle or a 96 mph Corbin Burnes cutter on the outside corner. The latter homer broke up a no-hitter.

The power surge is all the more impressive because Buxton is not missing his pitch and is already displaying better plate discipline. He ranks in the 61st percentile in whiff rate and has the same number of walks (2) as he had all of last year. The chase rate is down from last season, with the chase contact percentage going up.

Hopefully Buxton can stay healthy and put together a full season. He is showing signs of having an enormous campaign.

Richard W. Rodriguez/Associated Press

Joe Musgrove was probably the least notable of the three major acquisitions San Diego Padres general manager A.J. Preller made this offseason. 

That's no disrespect to Musgrove. It's just hard to have greater prominence when the team that traded for you already made separate moves for both Yu Darvish and Blake Snell. 

Yet, it's Musgrove who has looked the part of an ace.

The 28-year-old struck out eight in his season debut against the Arizona Diamondbacks on April 3. He then made history by becoming the first player in franchise history to throw a no-hitter, shutting down the Texas Rangers and striking out 10 in a 3-0 win Friday night. 

Musgrove was a popular breakout candidate entering the season. He has shown why he attained such a label, ranking in the 91st percentile in chase rate without conceding a single walk and striking out 18 in 15.0 innings.

Padres fans should feel quite optimistic about Musgrove, and not just because he threw a no-hitter. The California kid was already coming off a 2020 in which he ranked in the 93rd percentile in average exit velocity and 84th percentile in whiff rate.

Musgrove's batted-ball numbers have been slightly less encouraging in his first two starts of 2021, but the track record suggests he misses barrels and can generate whiffs. He is most certainly an arm to watch.

Jeff Roberson/Associated Press

The aforementioned Buxton homer is essentially the lone blemish on Corbin Burnes' absurd 2021 resume.

Burnes tossed 6.1 no-hit innings against the Twins in his first start on April 3, striking out 11 and thoroughly dominating Minnesota's dangerous lineup. His second start began more ominously, as St. Louis Cardinals utility man Tommy Edman began things with a leadoff triple. No matter. Burnes retired the next three in order and immediately strung together five no-hit innings. 

The 26-year-old has been terrific. He has 20 strikeouts and is yet to walk a batter, though he has hit a couple. Burnes ranks in the 73rd percentile in average exit velocity and 79th percentile in hard-hit rate. That is especially strong considering he also ranks in the 93rd percentile in whiff rate. 

Burnes' spin rates have always been terrific. But the key to success has been the cutter. He was more reliant on a straight heater early in his career, with opponents touching him up for 17 homers in just 49.0 innings in 2019. But he has gone to a fastball with cutting action that he can back up against lefties or front-door to right-handers.

The cutter plays so well because Brunes can also throw a two-seamer off it, and the slider also looks like a cutter out of his hands before it dives off the planet. That slider is actually averaging over two more inches of vertical movement than in 2020.

Burnes always had the stuff, but the cutter has seemingly unlocked his potential.

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If Burnes has been practically unhittable, Kansas City Royals right-hander Brad Keller has been anything but that.

Keller had a hard time just getting out of the first inning his first time on the bump, giving up seven straight baserunners and five runs in his Opening Day start against the Texas Rangers. He gave up two more hits and got just one out in the second inning before being lifted for a reliever. 

The second start did not go much better. Keller gave up six hits and four runs in 3.1 innings in Thursday's outing against the Chicago White Sox, serving up a pair of homers and walking three.

This is a guy who had a 3.08 ERA and 3.55 fielding independent pitching (FIP) mark in his rookie season in 2018. Keller had a 2.47 ERA and career-best 1.02 WHIP in 2020. What gives?

Well, Keller has never been a swing-and-miss guy. The batted-ball numbers are not all that stellar, either. He really has had success because he has managed to miss barrels. Even then, Keller outperformed his xERA in his first three seasons. 

It will be hard for Keller to have success if he does not get more swings and misses, particularly because his walk rates are also far from stellar for someone who does not generate a ton of whiffs. 

The early struggles could in fact be reflective of expected regression.

Derrick Tuskan/Associated Press

Is Evan Longoria headed for a late-career resurgence?

The 35-year-old has not had an OPS of .800 or higher since 2016. He has not hit above .260 since 2017. But Longoria is showing signs of a turnaround after his advanced numbers suggested he deserved better results in 2020.

Longoria is slashing .318/.400/.773 with three homers. He ranks in the 96th percentile in barrel rate and 76th percentile in hard-hit rate as well as the 94th percentile in xSLG. This follows a year in which the 2008 Rookie of the Year ranked in the 80th percentile or better in both exit velocity and hard-hit rate while also ranking in the 89th percentile in xSLG.

The key for Longoria has been his ability to keep the ball in the air. A big reason the advanced hitting stats did not translate to good numbers in 2020 was the 50.3 percent ground-ball rate. Well, Longoria is running his highest fly-ball rate and launch angle since 2016.

Remember, the three-time All-Star had a hot spring in which he slashed .346/.414/.885 with four homers. He is building on that and could put up surprising numbers if he continues to hit fly balls and line drives.

Mike Carlson/Associated Press

One of the more intriguing storylines to watch in Los Angeles was whether manager Joe Maddon would let Jared Walsh see an increasing amount of at-bats at first base or if he would still try to work in Albert Pujols.

Walsh has not only earned the right to be an everyday starter, but also helped key the Halos' early success.

The 27-year-old was slashing .375/.464/.833 with three homers, nine RBI and a triple in his first 28 plate appearances. Walsh had a two-homer game against the Chicago White Sox on April 4, with the second being a walk-off bomb. He has been yet another run-producer in what is shaping up to be a tremendous Angels lineup. 

Walsh is sort of like Yermin Mercedes in that he does not have the most outstanding average exit velocities (87.5 mph). But he ranks in the 90th percentile in barrel rate and makes a lot of contact, plus the max exit velocity (110.1 mph) points to his ability to hit the ball hard. 

Remember, Walsh was stellar in 32 games with the Angels last season, hitting .293 with nine homers and a 153 OPS+. Even if the slugging numbers start to go down, Walsh's hit tool makes him incredibly valuable in L.A.'s order.

Orlin Wagner/Associated Press

Who would have guessed that Nate Lowe would be leading baseball in RBI (14) through the first week of the season? 

The Texas Rangers acquired Lowe from the Tampa Bay Rays in December with the notion he would replace Ronald Guzman. He had a .770 OPS and 109 OPS+ in Tampa Bay, though he had just 245 plate appearances. Steadier playing time has served Lowe well.

Lowe ranks in the 82nd percentile in average exit velocity and 94th percentile in barrels, also ranking in the 96th percentile in max exit velocity. He has been dominant against right-handed pitching, with a 1.375 OPS against righties. Lefties have been more of an issue, as Lowe is hitting just .167 with a .397 OPS against them.

The Rangers might eventually consider giving Lowe some off days against left-handed starters. He started each of the first six games, with Texas facing lefty starters in half those contests.

All three of Lowe's homers have come with runners in scoring position. In fact, all three came with two outs and RISP. He has five hits in six plate appearances with two outs and RISP, an absurd number regardless of sample sizes. 

Lowe is already starting to cool, though. He is 0-for-11 in the last three games after going 0-for-4 Saturday night against the San Diego Padres.

Carlos Osorio/Associated Press

Akil Baddoo sure has made the most of his chance

The 22-year-old was the Detroit Tigers' Rule 5 draft pick in December. He had missed most of 2019 after undergoing Tommy John surgery and was robbed of playing games in 2020 because of the coronavirus pandemic. However, Baddoo wasted little time in making a name for himself in Tigers camp. 

Baddoo slashed .325/.460/.750 with five homers and four stolen bases in 21 spring training games. His excellent performance earned him a spot on Detroit's Opening Day roster. 

Things have only gotten better. Baddoo did not play in either of the team's first two games against Cleveland. But he homered in his debut on April 4 and earned another start the following day, going 2-for-4 with a grand slam.

Baddoo would make more of a hero turn in his third appearance, hitting a walk-off single. He ran his hitting streak to four games with an RBI triple Wednesday.

The barrel (20 percent) and hard-hit rates (40 percent) are quite encouraging. Baddoo also has the speed to leg out infield hits, and his max exit velocity (107.9 mph) projects well. 

The Silver Spring, Maryland, native will almost certainly come back to earth. He hasn't played above High-A ball, after all. But the Tigers could have a special player on their hands.

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Chicago Cubs closer Craig Kimbrel has had slow starts in each of his past two seasons. He was woeful in spring training, giving up nine runs in 6.2 innings.

It looked like the ninth inning could be a concern for the Cubs. Instead, the seven-time All-Star has resembled the dominant closer of old.

Kimbrel has struck out nine opponents in his first 4.2 innings while retiring all 14 batters faced. He has converted both of his save opportunities, including the first five-out save of his career Thursday afternoon against the Pittsburgh Pirates after he worked out of a jam in the eighth.

The 32-year-old ranks in the 87th percentile in average exit velocity and 90th percentile in whiff rate. But the most important nugget is Kimbrel ranking in the 97th percentile in chase rate. 

The latter figure indicates Kimbrel's nasty stuff has returned. Cubs shortstop Javier Baez said after Thursday's win opponents are even telling him Kimbrel resembles his past self. 

Kimbrel does seem to be finding his stride. He is elevating the fastball with good run, and he has a better release point with the knuckle curveball this year than he has in the last couple of seasons. 

The multiple-time Reliever of the Year built confidence at the end of 2020. He has started 2021 with even more confidence, which could make him a valuable asset—and possible trade chip—at the back end of Chicago's bullpen.

David Zalubowski/Associated Press

Colorado Rockies infielder Ryan McMahon owes much of his success to one game in particular. 

McMahon served up the first three-homer contest of the season with an enormous performance against the Arizona Diamondbacks on April 6. He added a double to the three dingers.

The 26-year-old hadn't been overly impressive outside that performance, but he clubbed another homer Saturday against the San Francisco Giants.

McMahon has terrific batted-ball numbers for a guy who has avoided previous strikeout issues. He ranks in the 84th percentile in average exit velocity and 71st percentile in barrel rate.

Like Longoria, McMahon is starting to launch the ball. He had a ground-ball rate above 50 percent in each of the past two seasons but is at 19.2 percent in 2021.

McMahon could experience issues if the whiffs return, especially since he has the highest swing rate of his career early on. Past strikeout issues would suggest he will come back to the pack.

Still, McMahon has an obvious power stroke. He hit 24 homers in 2019 and could hit 30-plus if he keeps the ball in the air, especially given he plays home games at Coors Field.

All stats obtained Baseball Reference, Baseball Savant or FanGraphs, unless otherwise noted. Stats are accurate prior to the start of play on April 10.