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If All-Star voting ended today, two of the three starting outfielders for the National League would be repeat representatives. The leading vote-getter, Matt Kemp, made the team last season and went on to be runner-up in the NL MVP race. Behind Kemp is Carlos Beltran, who’s been to six All-Star games.  

But the player who recently displaced reigning MVP Ryan Braun to take over third place has never been an All-Star. He’s never come close to winning any major awards or leading the league in any important statistical category. He’s been a punch line and an afterthought, but before this season, he’d never been one of baseball’s best players.   

That third-place player is Melky Cabrera, who has undoubtedly been one of baseball’s best players in 2012. Even after an 0-for-4 performance against Jered Weaver on Wednesday night, Cabrera is batting .363. He leads the NL with 101 hits, and among NL players, he trails only Joey Votto and David Wright in Wins Above Replacement Player (WARP).

One other stat about Cabrera stands out: like Kemp, who was having a spectacular season of his own before hurting his hamstring, he’s 27 years old. In his 1982 Baseball Abstract, Bill James observed that “both pitchers and non-pitchers attain their greatest aggregate value at the age of 27.” Since then, 27 has been widely regarded as an age of special seasons. Each spring, writers release lists of players primed for age-27 “breakouts,” and fantasy players pick them up, expecting to receive career years in return. If Cabrera keeps this up, he’ll be a perfect example of a 27-year-old player who delivered a dramatically different level of production than he had at 26.

However, it might be premature to proclaim Cabrera the poster boy for an age-27 effect. In fact, there’s little evidence to suggest that breakouts happen more often at 27 than they do at other ages, and good reason to think that calling Cabrera’s 2012 a breakout would be overblown.

Last year, Baseball Prospectus author Derek Carty did a study designed to detect the alleged age-27 breakout effect. Carty looked at all players since 1953 with at least one season of 400 plate appearances or 130 innings pitched, then compared each player’s numbers in each such season to his numbers in the next, grouping the players by age. He defined a “breakout” as a season in which a player outperformed his previous year’s production by at least 20 percent, though he later repeated the study with the minimum improvement set to 10 percent and 30 percent.

No matter where Carty set the cutoff, he couldn’t find any evidence that age-27 seasons were especially likely to lead to breakouts. The results showed that the highest breakout rates were associated with earlier ages: ages 22 through 26 all yielded higher breakout rates than age 27. Hitters were no more likely to have breakouts at 27 than they were at 36.

It’s reasonable to expect a player to post a peak season at 27, but as Carty pointed out, his actual improvement in that season will almost always be incremental. In most cases, players who had peak years at 27 were almost as good at 26.

By all appearances, Cabrera is an exception to the rule of incremental age-27 improvements. His first few months have been fantastic—especially his .429/.457/.647 May—and barring a severe slump in the next few weeks, he’ll have earned a starting All-Star spot. However, what appears to be a breakout now might look a lot more like an incremental improvement by the end of the year, since the development most responsible for Cabrera’s success isn’t likely to survive the second half.

Cabrera’s walk and strikeout rates are almost identical to their 2011 level. He’s not hitting home runs more often, and the percentage of his hits that have gone for extra bases is lower now than it was last season. The improvement in his surface statistics is almost entirely attributable to one change: he’s hitting singles in about 30 percent more of his at-bats than he did last year.

Unfortunately for the age-27 breakout believers, Cabrera’s current rate of hitting singles isn’t sustainable. His .404 batting average on balls in play is the second highest in baseball, behind only Joey Votto. Only four players have ever recorded a BABIP above .400 in a season of at least 500 plate appearances: Roberto Clemente, Rod Carew, Manny Ramirez, and Jose Hernandez. Hernandez was the last to do it, in 2002. Cabrera’s career BABIP is almost 100 points lower than his 2012 mark, and his expected BABIP based on his batted-ball statistics is roughly 50 points lower than that .404 figure. Take 50 points of batting average away from Cabrera, and his numbers start to look a lot more like they did in 2011.

That’s not to say that Cabrera is no better now than he was last season. His plate discipline statistics paint a picture of a player with an improved approach:


Swing %

O-Swing %

Z-Swing %

Contact %











Cabrera is swinging less often overall, but he’s actually swinging more often at pitches inside the strike zone. The reduction in his swing percentage is entirely attributable to a decreased tendency to go after pitches outside the zone. Since he’s laying off pitches he probably couldn’t have hit anyway, he’s making more contact when he does decide to swing. More contact means more balls in play, and more balls in play mean more hits.

Since a higher percentage of Melky’s swings have been aimed at hittable pitches, he’s probably making harder contact as well as more frequent contact, so it’s reasonable to expect more of the balls he puts in play to become hits. He’s also hitting more ground balls, which tend to become hits more often than balls hit in the air (albeit not the extra-base kind). And while conditioning has been a problem for him in the past, he’s worked hard to get in shape, which may be helping him eke out a few hits he wouldn’t have otherwise.

All of those factors point to an improvement, but only an incremental one typical of a player at his peak. That’s not bad news for San Francisco. Although his terrible 2010 made more of an impression on most fans, Cabrera was worth four wins to Kansas City last season, so a Cabrera who’s just a bit better than that is still an extremely valuable player.

As good as Cabrera has been, anyone stubbornly holding out hope for the age-27 breakout theory might be better off using the Rays’ Matt Joyce as an example. Joyce’s improvement isn’t dependent on a BABIP boost. Like Cabrera, he’s shown a more refined approach at the plate, but his maturation has manifested itself in patience and power, not an ephemeral average. As a result, he may have a better chance of being the same player at the end of the season as he’s been so far.

It’s easy to find examples of players who’ve made major improvements at age 27, but the opposite is also true. For every Melky Cabrera or Matt Joyce, there’s a Drew Stubbs, Brennan Boesch, or Ryan Zimmerman enduring a down year at what’s supposed to be his peak. It’s fair to expect career years from 27-year-old players—Cabrera included—but breakouts are a bridge too far.  

A version of this story originally appeared on ESPN Insider Insider.

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Good article, Ben, but the underlying premise of using Melky Cabrera for an analysis of a supposed age-27 breakout is flawed. Melky Cabrera's breakout season was LAST year, not this year.
If what he's doing now were real, wouldn't that also qualify as a breakout? An even bigger breakout?
I know ATT Park is not generally considered a hitters park, but could it be that it just fits Melky's new hitting approach better than Kauffman Stadium, Turner Field or Yankee Stadium ever did? ATT is great at diminishing the numbers of power hitters, but for guys like Cabrera who are hitting more singles, perhaps it is actually easier to hit into the gaps, which would help inflate his numbers further.
I know this sounds improbable, but is it possible to interpret that high BABIP indicates hitter's ability to hit the balls into the gap? (I admit Joey Votto sparks that idea in my mind more then Melky does.)
To be fair to Bill James it should be pointed out that he didn't talk about players "breaking out" at age 27. His point was that players tend to peak at 27. If I remember correctly he was responding to the common assertion back then that hitters peaked in their early thirties. It didn't require a lot of heavy math to show that players peaking in their early thirties was the exception.

I agree that fantasy players drafting every 27 year old expecting huge improvements is a lot of nonsense. But the idea underlying this is not crazy. 26 year olds tend to get better. 32 year olds tend to decline. This is a fact of life that any general manager, fantasy or otherwise, ignores at his peril.
Right, James didn't talk about age-27 breakouts, and I certainly didn't mean to suggest that he did. If anything, his conclusions have been misinterpreted by some.