Don't Be Shocked If John Mayberry Falls Flat on His Face

Nobody reading this needs to be reminded of what a pleasant surprise John Mayberry Jr. was in 2011. He had a great year, which went something like this: After reportedly showing up in Clearwater in great shape, Mayberry had a strong spring training, going 20 for 68 with 5 HR, 6 BB, 12 K, and 4/4 SB, earning himself a bench spot on the Opening Day roster. Then on Opening Day itself, he came up with a game-winning walk-off RBI pinch single. He stayed hot through April but then started to struggle in May, especially after being forced into the starting lineup for 18 games (68 PA) beginning on May 15 due to a Shane Victorino injury (.194/.265/.323). When Victorino returned, Mayberry was optioned to Lehigh Valley. But then he returned on July 5 and went buck wild as a part-time starter for the rest of the season. His wRC+s for July, August, and September were 158, 175, and 146, respectively. In total, he hit 12 HR and .301/.358/.607 over his last 179 PA and ended the season with 2.5 fWAR in only 296 PA.

It was tremendous, and he deserves a lot of praise for it. But that doesn't mean he'll be able to repeat it over a full season in 2012 -- or ever. Mayberry was 27 in 2011 and it's common for players to get a lot better around that age. But the degree to which Mayberry appeared to improve last year has got to raise a healthy amount of suspicion that maybe what we saw was too good to be true. While Mayberry was once a first-round draft pick and therefore isn't completely without a prospect pedigree, he was a pretty pedestrian hitter for his entire career prior to 2011, and that isn't something we can just throw out the window just because of one season of great stats in part-time duty. And especially since in Mayberry's case, he didn't even really put up one season of great stats -- he really only put up three months of super-awesome stats. Below the jump is a chart (italicized numbers are back-of-the-envelope ballpark estimates).

This chart has a bit of a Rorschach quality to it and is subject to a certain amount of individual interpretation, but at the same time, WTF it's totally weird. Apart from some (mostly meaningless) good stats and subjective praise from spring training, there was basically zero reason on July 4, 2011 to believe that Mayberry had changed in any way. His stats until that point were entirely consistent with what you would have thought of him on January 1, 2011: that he was a 27-year-old non-prospect who had topped out as a mediocre AAA hitter and would never be anything more than a backup in the big leagues. His breakout was abrupt, could not have been foreseen, and occurred over a pretty modest sample size.

The implications of that are unclear. On one hand, Mayberry was so awesome over that small sample that it was enough to make even his cumulative stats look good. A mere 179 PA of a 159 wRC+ may be very weak as evidence that Mayberry has turned into a 159 wRC+ hitter, but as evidence that he's turned into an above-average hitter, it isn't nearly as weak. On the other hand, 179 PA is 179 PA -- the equivalent of roughly 40 games for a typical everyday player.

I guess I'd like to open this up for some crowdsourcing, if I might. First, can you name any hitters whose career trajectories would be precedents for Mayberry being the real deal going forward -- guys who showed little promise in the minors long past age 25, then suddenly put it all together? (Don't include guys whose early-career struggles were due to extenuating circumstances such as injuries or drug abuse.) Second, can you name any mediocre or below-average hitters who put together 40-game stretches of awesomeness, then went back to being themselves? Call me a pessimist, but I suspect that there will be more answers to the second question than the first.

I want to be clear: I'm not saying that Mayberry is definitely going to fail. I'm not even saying that he's probably going to fail. But I am saying that the possibility that he'll fail is far from remote. And my subjective impression is that far too few Phillies fans these days, even in the saber community, are sufficiently cognizant of that possibility. YMMV, but I personally think Mayberry's chances of failing in 2012 are substantially greater than Domonic Brown's. A lot of people seem to be taking the reverse for granted.

If Mayberry goes back to being what he was (a league-average hitter in AAA, which probably is equivalent to around a 90 or so wRC+ hitter in MLB), then he probably won't be an acceptable starting corner outfielder. In 2011, LFs who put up those kinds of hitting numbers were in the neighborhood of 1 offensive WAR, which isn't good. You can compensate for that with defense to an extent, but unless you're truly extraordinary out there, defense alone won't make you a league-average player. Interestingly, Mayberry did have extraordinary UZR stats in 2011 (+27.7 UZR/150 in 161.1 innings in LF, which is nearly Brett Gardner territory, along with +18.6 UZR/150 in 66.1 RF innings and a respectable -5.6 UZR/150 in 246.2 CF innings), but I have serious doubts about the predictive value of those numbers, considering that a few hundred innings is a tiny sample for UZR purposes -- for instance, Carlos Lee had a +18.1 in 645.1 innings as a LF last year. Mayberry never had a reputation in the minors for being any sort of defensive whiz, and while I'd love to be proven wrong, I don't expect that the Gardner model will be a viable ticket to long-term success for him. He's got to hit. And he may not.

This is not to suggest that the Phillies are doing anything wrong by handing Mayberry the LF job in 2012. It's well worth the risk of failure to find out if Mayberry can succeed, especially since the Phils will also have Dom Brown waiting in the wings in AAA as a backup plan. Nevertheless, there is a risk. Even if worst comes to worst, Mayberry won't kill the 2012 Phillies. After all, Raul Ibanez had a 90 wRC+ last year and he didn't kill the 2011 Phillies. (And Ibanez was a bad fielder to boot. No matter how flukish Mayberry's 2011 UZR may have been, he'll almost certainly be a substantial step up in the field compared to his predecessor.) But the Phillies won't always be as strong at their other positions as they are now, and if Mayberry turns out not be the long-run answer, that will affect the decisions the front office will need to make for 2013.

[h/t WL for his helpful feedback and PF for crunching some numbers I used above]