Jacoby Ellsbury had a fine debut in pinstripes last season. It wasn’t quite as good as his walk-year from Boston, but he certainly didn’t fail to reach expectations. His defense was superb, as expected. He stood out on the basepaths, as expected. He hit well, as expected, just not quite as well as he did in his walk-year with Boston. That year, 2013, Jacoby batted .298/.355/.426 (113 wRC+). In 2014, his triple-slash fell to .271/.328/.419, although his performance relative to the league (107 wRC+) didn’t dip quite as much thanks to a power surge (16 home runs, 7 more than prior year). All told, Jacoby accumulated 3.6 fWAR. That’s very good, but perhaps it was the type of performance we expected in year two or three of his seven year contract. Should we be worried that Ellsbury’s decline has begun?
Speed is obviously integral to Jacoby’s game, and the narrative is that players who rely on their legs fall off quickly as they slow down. It seems logical that a player’s defense and baserunning might take a hit as he slows down. One might lose some infield hits or be unable to take the extra base, too. Yet, there are indications that speedy players age better than others, and Ellsbury has additional evidence from late last season that makes his offensive statistics look deceiving in retrospect.
On August 29, Ellsbury sprained his left ankle, forcing him out of a few games. Just a few weeks later, Ellsbury strained his hamstring, forcing him out of the team’s final nine games. That sure seems to explain his dreadful September, rather than considering it a slump, random variation, or just a mere coincidence. Perhaps it’s reasonable to expect his 2015 to be similar to his April through August performance last season, if healthy. Staying healthy has been a challenging for Ellsbury, of course. It might be a reach to expect him to not have any sort of malady this season, which in turn could bring down his numbers like last September did. Even so, I think it’s a pretty good bet that his full-season numbers will easily surpass that of 2014.
ZiPS and Steamer both foresee Ellsbury taking a step back from his April through August statistics. Steamer practically estimates a carbon copy of 2014 for Ellsbury’s upcoming year: .272/.329/.418. I’m definitely taking the over on that. On the other hand, ZiPS is more optimistic, forecasting a triple-slash of .281/.337/.424. This projection seems to acknowledge that Ellsbury’s 2014 numbers didn’t reflect his true talent level, likely thanks to his wounded September. My guess is more in line with ZiPS estimate, although I think I’m a little more bullish on Jacoby than the system.
While nobody was probably concerned about Ellsbury’s upcoming season, it’s worth noting that Jacoby appears to be a candidate for positive regression to the mean this year. He’s essentially a lock to outperform his overall 2014 line, and a pretty good bet to beat the projection systems too. Let’s just hope he can avoid any debilitating injuries like last September.