Should the Rangers sign Prince Fielder?

With rumors that the Jays submitted a “monster bid” for NPB pitching sensation Yu Darvish, and the Rangers having lost out earlier in the year on C.J. Wilson, conversation inevitably turns to the final major free agent the Rangers have been linked (albeit tenuously) with, Prince Fielder. Is Prince a good investment for the Rangers?

First, let’s examine his career thus far. Fielder has been a remarkably healthy player, averaging nearly 700 PA per season. He has also just recently cut his K%, from a career of mostly 19% down to 15% in 2011. These are certainly encouraging signs from a player entering his prime. However, some questions remain. His year to year variation in offensive output is troubling. From 2006-2011, his year to year wRC+ was 111, 152, 125, 160, 137, and 162.

His BABIP, K%, and BB% have been consistent throughout, but his .ISO has followed his wRC+ (.213, .330, .231, .303, .209, .267). Compare his rates to Albert Pujols, who save for the 2007 season had a wRC+ between 165-185 for the period 2003-2010. Perhaps Boras’s now-famous “accomplishment book” for Fielder will shed some light on the mystery.

Apart from his offensive ability, Fielder has been below average in both fielding and baserunning throughout his career, although there are suggestions from writers and team executives that his fielding abilities are underrated.

From a review of his statistics and his evaluations by sources from around the league, we can safely conclude Fielder is an excellent first baseman.

According to Jon Heyman of CBSSports.com, Scott Boras is seeking a deal similar to that of Pujols for Fielder, which is to say for 10 years with an average annual value of $25 million or so. Assuming $5 million nets you 1 WAR and that $/WAR inflates at 5%, over the lifetime of a 250/10 yr contract Fielder would need to produce roughly 37 WAR. Last season, Fielder was worth 5.5 WAR. Assuming his peak years are ages 28-30, and he produces 5.5 WAR or so in each of those years, and then begins a decline phase, losing .5 WAR per season, he will produce 41 WAR, roughly matching the value of the contract.

Of course, given his build, genetic history in the form of his father, and the more rapid decline profile of heavier sluggers and star players in general, this likely represents an optimistic projection for Fielder. Nevertheless, he is unlikely to be wildly overpaid given his contract expectations.

Were the Rangers to sign Fielder, he would replace a platoon of Mitch Moreland and Michael Young, with Mike Napoli getting PA whenever he needs rest. Last season, despite struggling with a wrist injury starting in mid-June, Moreland had a wRC+ of 104 against righties, Michael Young hit 141 wRC+ against lefties, and Mike Napoli, in his breakout season, mashed lefties and righties evenly at 179 wRC+.

While it is difficult to predict the WAR of that trio without having a better idea of their PA distribution, there is little doubt that Fielder would be an offensive upgrade, assuming he maintains last year’s pace. Defensively, he would probably represent a slight upgrade or a tie.

In short, signing Fielder would make the Rangers a better team without excessively sacrificing payroll flexibility in the future, especially if Josh Hamilton is not resigned after 2012.

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