Prince Fielder Comps

I don't have much new to add to the Prince Fielder hubbub, but I did crunch a bunch of numbers to average what his top 10 similar batters through the age of 27 did in the next nine years of their careers. The numbers reflect what everyone except Mike Ilitch expects: two or three more highly productive years followed by a sharp decline during the bulk of the insane nine year contract. I expect Fielder to outperform the average of his comps by a bit—he has averaged 4.4 fWAR over the last five seasons, so it would be reasonable to expect similar production for the next couple of years, whereas his comps project just a 3.3 WAR in 2012 and '13. Fielder has been incredibly durable so far in his career, and his comps don't keep up with his playing time (of course, he probably won't be able to either). Still, I would hate to have the last five or six years of that contract looming over my team's future. The problem for the Royals of course is that Fielder's remaining productive years may overlap with what is the Royals hoped for window.

Here is the boring explanation of the below numbers: The top is Fielder's actual career to date, and the bottom is the average of his top 10 comps. To get the WAR numbers, I took the OBP & SLG of his comps and plugged them into this spreadsheet. I set the league average wOBA to .325, and rated Fielder at -5 UZR/150 at first base for each season (which is kind since he has been a -6.4 over his career and should only get worse). I also plugged the numbers in at DH, but it turned out WAR came out almost exactly the same for a -5 UZR/150 first baseman as for a DH. The last line totals the age 28-36 average seasons of his comps.

So nothing earth shattering here. Fielder joining the division is probably bad news for the Royals in the short term and good news in the long term.