Manny Machado is unarguably going to be a star for a long time, but is it possible that breakout stars like Patrick Corbin and Josh Donaldson could be one-hit wonders?
With all due respect, not everyone who has a great season is going to follow it up with a comparable season any time thereafter.
Just in 2009 alone, Jason Bartlett, Chone Figgins, Franklin Gutierrez and Nyjer Morgan each posted a WAR of least 5.0.
Morgan (3.6 in 2011) is the only person from that group to have a single-season WAR of more than 2.2 since.
Some players disappear from the spotlight just as suddenly as they got there.
Of this season's 13 breakout stars—as defined on the next slide—there are at least five who are destined to follow the unmemorable career arc of Junior Spivey.
*Unless otherwise cited, all statistics are courtesy of FanGraphs and are accurate through the start of play on Thursday, Aug. 8.
For some articles, I use upward of 10 criteria to whittle the field of players down to a more manageable number, but this one is short, sweet and simple.
In order to be considered a breakout star, the player must both be a breakout and a star. Thank you, Captain Obvious, right? Well, let's put some numbers behind that rationale.
To be a star in 2013, the player must have a WAR of at least 3.5 if a batter or 2.5 if a pitcher—according to FanGraphs. Conveniently, this leaves us with 32 batters and 32 pitchers.
To be a breakout star, the player's WAR in 2013 must be at least 50 percent of his career WAR. This seemed to be the most objective way of removing players like Miguel Cabrera and Buster Posey, who are clearly stars but have also been stars for a little while now.
As you'll see on the next several slides, determining whether those seven pitchers and six batters are one-hit wonders was a little more subjective.
Jose Fernandez: 2.9 WAR in 2013, 2.9 career WAR
Matt Harvey: 5.6 WAR in 2013, 6.7 career WAR
Manny Machado: 4.8 WAR in 2013, 6.1 career WAR
There's no reason for me to dedicate an entire slide to each of these guys.
Barring some sort of horribly unfortunate, career-altering injury, no one in their right mind would argue that any of these three players will fail to appear in at least five more MLB All-Star Games in their career.
Beyond All-Star appearances, Machado is headed for at least half a dozen Gold Gloves, and it would be somewhat surprising if Harvey and Fernandez didn't combine for four or more Cy Young Awards over the next decade—starting with the one that Harvey could be getting this season.
Maybe I'm overstating their end-of-season award potential due to my proximity to Baltimore and my allegiance to a team in the same division as Harvey and Fernandez, but these three players are the furthest thing from consideration as one-hit wonders. It's going to be fun to watch them over the next (hopefully) 15 to 20 years.
Player: Patrick Corbin
2013 WAR: 3.3
Career WAR: 4.6
Primary statistics leveraged in assessment: BABIP, LOB%, HR/9
Verdict: One-hit wonder
I don't actively want to hate Corbin, but the peripheral statistics still make him difficult to trust.
It would be one thing if he just had the sixth-highest LOB percentage in the majors. Or if he was just getting lucky with his home run rate. Or if his BABIP wasn't at least 50 points lower than any other stop in his career in which he made at least 10 appearances.
But to have all of those things working in his favor at the same time? It's downright terrifying. I already feel terrible for the poor soul who drafts him in the sixth round in fantasy leagues next season.
Corbin has had a terrific season and 100 percent deserved his trip to the All-Star Game. I'm not trying to take any of that away from him, and I'm sure he'll be a more-than-serviceable middle-of-the-rotation type of pitcher for many years.
I just don't suspect we'll see him competing for an ERA crown this late into any other season in his career.
Player: Paul Goldschmidt
2013 WAR: 4.5
Career WAR: 7.9
Primary statistics leveraged in assessment: OPS, wRC+
As something of an olive branch to Diamondbacks fans upset about the previous slide, I had no trouble whatsoever giving Goldschmidt a star verdict.
There are a grand total of five players with a wRC+ (essentially a bell curve of runs created, in which 100 is average and higher is better) of at least 150 and scores in both baserunning and fielding that aren't detrimental to their team.
Goldschmidt is one of those players. The other four are Carlos Gonzalez, Andrew McCutchen, Joey Votto and David Wright.
That's pretty good company for a player who doesn't turn 26 for another month.
Goldschmidt's OPS is the eighth-best in all of baseball this season and is currently the 27th-highest single-season OPS for a player under the age of 26 over the past decade. Of the 26 ahead of him on that list, only Carlos Quentin's 2008 season stands out as belonging to someone who didn't have a multiyear run as a surefire All-Star.
Player: Eric Stults
2013 WAR: 2.6
Career WAR: 4.3
Primary statistics leveraged in assessment: K/9, HR/FB, age
Verdict: One-hit wonder
Of the 13 names on the list, Stults was easily the most surprising to me. I knew he was pitching well because I have him in two of my three fantasy leagues, but I wasn't expecting upper-echelon numbers.
Nor do I expect them in subsequent seasons.
There are currently 21 pitchers who have logged at least 150 innings on the season, and only Bartolo Colon averages fewer K/9 than Stults. The league leaders are averaging nearly twice as many strikeouts as him.
There's more to pitching than just strikeouts, but it's pretty hard to be a star pitcher in this game while barely averaging four strikeouts per game.
Stults also has an alarmingly unsustainable rate of home runs allowed. He has allowed the lowest percentage of home runs on fly balls while also allowing more fly balls than any of those other 20 pitchers.
A low ground-ball rate coupled with a low strikeout rate and an extremely favorable home run rate is a formula for regression if I've ever seen one.
Throw in the fact that he turns 34 this offseason and had a combined WAR of 1.7 from 2006 to 2012, and it's pretty hard to expect him to be a prolonged star in the majors.
Player: Starling Marte
2013 WAR: 3.9
Career WAR: 5.0
Primary statistics leveraged in assessment: BB rate, K rate, BABIP vs. AVG
Verdict: One-hit wonder
Based on the picture above, you can probably venture a pretty good guess as to who that person is.
If not for J.P. Arencibia, Marte would be tied for the worst BB/K ratio in the league. Meanwhile, his BABIP is 75 points higher than his batting average. That's not quite as bad as Mike Napoli's 116-point difference, but it's still pretty bad.
Speedy players who strike out on a regular basis typically have a pretty big differential, though. Drew Stubbs has a career batting average 84 points below his career BABIP because he strikes out nearly 30 percent of the time and doesn't hit a ton of home runs. It's a similar story for Austin Jackson and B.J. Upton, who have a differential of 85 points and 68 points, respectively.
Would you really classify any of those players as stars, though?
Upton was a borderline star before completely tanking this season, but this type of player is susceptible to cold spells when he's both striking out in bunches and not getting friendly bounces.
But an annual star? I just don't see it.
Player: Hisashi Iwakuma
2013 WAR: 2.6
Career WAR: 3.2
Primary statistics leveraged in assessment: K/BB, xFIP, career in Japan
Statistically, he seems like the real deal.
He's averaging five strikeouts per walk and has a sub-3.00 ERA despite the second-least-fortunate HR/FB ratio among the 27 pitchers with an ERA below 3.20. He does have a very low BABIP, but he's also a ground-ball pitcher who spent half the season with the best fielding shortstop of the past five years behind him.
If he wasn't from Japan, he might be one of the first 10 pitchers off the board in fantasy drafts next season. As is, people are hesitant to believe in him.
Including active players, there have been 38 MLB pitchers from Japan. For every Hideo Nomo who had a long and largely successful MLB career, there are a handful of pitchers like Kazuhisa Ishii, Daisuke Matsuzaka and Hideki Okajima, who pitched well at first only to start unraveling in their third season in America.
I believe in Iwakuma, though. In just the six years since Dice-K's arrival in the U.S., we've learned a lot more about how to forecast regression. Looking back on Matsuzaka's first two seasons, it's no surprise that he fell apart. He was a fly-ball pitcher with an unsustainable BABIP and awful walk rate.
Even though he's already 32 years old, if Iwakuma can keep his walk rate down, he'll be a star in this league for at least another five years.
Player: Josh Donaldson
2013 WAR: 4.5
Career WAR: 5.8
Primary statistics leveraged in assessment: Career batting average and preseason projections, month-by-month splits
Verdict: One-hit wonder
Coming into this season, Donaldson had 2,630 career plate appearances between the minors and majors. That's roughly four full seasons' worth of data points, and Donaldson was projected by both ZiPS and Steamer for no more than 180 plate appearances and a mediocre batting average.
Even in retrospect, it was a pretty fair assessment.
He had made five different stops in his career in which he received at least 250 plate appearances, and his batting average ranged from .217 to .270 in those largest sample sizes.
Despite those numbers, Donaldson batted .322 over the first two months of the season and carried a .310 batting average into the All-Star break.
He's finally coming back to earth, though. In 18 games since the break, he's batting .206 with one home run and five more strikeouts than hits.
He'll be an OK player and should hang on to the starting third base job in Oakland for another few years, but 2013 was the last time he'll even be considered a snub for missing the All-Star Game.
Player: Felix Doubront
2013 WAR: 2.8
Career WAR: 4.9
Primary statistics leveraged in assessment: BB rate, HR/FB ratio, xFIP, durability
Verdict: One-hit wonder
Doubront has a control problem.
In addition to his susceptibility to walking a lot of batters, he's been pretty fortunate in the HR/FB department this season. On a leaguewide basis, 10.6 percent of fly balls result in home runs. Only 7.1 percent of Doubront's fly balls have left the yard.
When that number regresses to league average, it's not hard to imagine his ERA ballooning, based on the likelihood that those home runs will also be driving in runners on base via walks.
Regarding the durability concerns, the controversial innings limit placed on Stephen Strasburg last season was only 160 innings—a number that six pitchers have already reached this season with approximately 10 starts remaining. Doubront turns 26 this October, and 2012 was the only calendar year in which he reached 130 innings pitched.
Though people have gone gaga over Strasburg in recent years, it's hard to be a star pitcher without at least reaching 180 innings on a regular basis—a number that Justin Verlander is going to surpass for an eighth straight season.
Player: Chris Davis
2013 WAR: 5.3
Career WAR: 6.2
Primary statistics leveraged in assessment: HR
Davis is going to join that club of prestigious names before the end of August and could potentially still hit 60 home runs this season.
Player: Jose Quintana
2013 WAR: 2.8
Career WAR: 4.5
Primary statistics leveraged in assessment: ERA, K/9, pitch type, swinging strike percentage
Verdict: Too close to call
I simply have no idea what to make of Quintana.
If not for a WAR in the top 25 among starting pitchers, I'd say he's a perfectly average pitcher. There are 91 qualified starting pitchers, and Quintana is neither in the top 30 nor bottom 30 in K/9, BB/9, HR/9, BABIP, ERA, FIP or xFIP.
He isn't great at anything, but he isn't terrible at anything either. Comparing him solely to other White Sox pitchers, he's clearly nowhere near as good as Chris Sale, but he's also certainly better than Dylan Axelrod.
My gut says he's the definition of an average pitcher, but somehow beat the sabermetrics system to even show up on this list.
If you don't play fantasy baseball or live in Chicago, there's no good reason for you to even know who Quintana is. That alone should keep him from being considered a star, but he's also only 24 years old.
Who knows? Maybe 2014 will actually be his breakout year.
Player: Matt Carpenter
2013 WAR: 4.3
Career WAR: 5.6
Primary statistics leveraged in assessment: WAR, career AVG and BABIP, BB/K
When I look at Carpenter, I see a lot of Ben Zobrist.
Zobrist has more power and speed on the basepaths, while Carpenter is better at actually getting on base. However, they both have the ability to play a number of different positions while racking up a high WAR that makes them much more highly regarded in the sabermetrics community than in the real world.
Did you know that Carpenter has a better OPS than Jay Bruce or Allen Craig? Or that he's tied for eighth in the National League in on-base percentage? What about the fact that he has created more weighted runs than Justin Upton or Buster Posey?
I was one of Carpenter's biggest supporters during the All-Star balloting portion of the season, and I didn't even realize he was doing that well in those categories.
He'll probably never be a superstar, but it seems he could quietly be one of the most valuable players in the game for years to come.
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