Quantifying Jacoby Ellsbury's Value

As a fan of the Boston Red Sox, it is clear to me that fans love Jacoby Ellsbury because he is a handsome man and because he is an exciting ballplayer. His scouting report coming out of Oregon State as a first round pick in 2005 suggested that he was essentially a 4-tool player with blazing speed, but very little in terms of power projection. He put the ball in play and was a gap-type hitter who projected to be similar to Johnny Damon, but with less power. It was projected he would be a plus defender, but I always found it odd that Baseball America considered Ellsbury a top 20 prospect considering his lack of impact power. It was not like he had Dexter Fowler's power potential, but they were ranked similarly for awhile.

Between Ellsbury's 2005 stint at SS Lowell and his 2007 stint at AA Portland, Ellsbury routinely walked almost as much as he struckout, and he never struckout in more than 12% of his PA. He was excellent at putting the ball on the ground, never averaging less than 56% of the balls he put in play on the ground, and he continually raised his Line Drive percentage as time went on, as well, as it morphed from 10 to 14 to 16% on his rise to AA. Of course, with the exception of a very brief stint of power at AA in 73 PA, Ellsbury never posted an IsoP over .126, so he was living up to what could be expected. 

After those 73 PA in 2007 at AA, Ellsbury was pushed to AAA, where his IsoP dropped below .100 and his slugging percentage sat at just .380. Still, he maintained his K% at 11% and continued to put the ball on the ground effectively. He posted just a .740 OPS at AAA as a 23-year-old, but it was on-base heavy and the Red Sox were desperate to energize the team with a struggling Coco Crisp playing center at the time. Ellsbury delivered at a better clip than his performance at AAA, raising his IsoP all the way up to .156 and and maintaining a steady K% around 11%. Of concern was a diminishing walk rate, as he walked just 6.3% of the time he appeared, but it is hard to nitpick with a near .900 OPS in his debut.

2008 saw a not surprising return to the player who had some problems at AAA, and who also had some problems competing for a job with Crisp. After struggling much of the season, he managed to hit .280, but he struckout an alarming 13.2% of the time, which is very high for a guy that lives on making contact and using his speed. It did not help his cause that his BABIP was an unusually low .312 for a player with his speed. His IsoP dropped to .118, but that was largely in line with his minor league numbers. Additionally, Ellsbury's RZR rating would rank him as the eighth best centerfielder in baseball last year, in terms of outs that he recorded on balls in his zone. 

To me, Ellsbury is a case of managing expectations. He is not, and never was, worth the label he got as a "top" prospect. What he can do is provide you with above average defense, steal 50 bases with a high percentage, and get on base. The two things that Ellsbury needs to work on are putting the ball in play more consistently so that he can take advantage of what should be an improved BABIP, and he needs to control the strikezone. I'd like to see his K% numbers under 11 this season, and his BB% numbers approaching that, as well. He is not generating enough power to do otherwise. Still, he stands the potential to be a very useful player if he can improve on his .280 average, which he should. 

As a current update, he's hitting .289 right now, but the BB% is a very weak 5.2%. On the bright side, his K% is just 8.2%, so he's definitely putting the ball in play. Unfortunately, his GB% is at a career low 51% and his IsoP is at a miserable .067, which is a suggestion of no power at all. He looks like he has a Placido Polanco-esque line right now, and he's capable of more than that.