Can a player, no matter how productive on offense, be voted a league Most Valuable Player if he is rated the major leagues' worst defensive player at his position? This is the test case that Curtis Granderson presents. Granderson is having a monster season at the plate, on pace to set career bests in many categories. He has been the most consistently productive hitter in a Yankees' lineup that is headed to the postseason and perhaps a division title. However, defensive metrics say Granderson is the worst defensive center fielder in baseball. So, can he be the AL MVP?

Granderson is hot. The Yankees begin a weekend visit from the Rays with their center fielder hitting .333 with four home runs, 11 runs and 15 RBIs in 10 games this month. He is batting .275 overall and has already set career highs with 32 home runs and 93 RBIs. Granderson is also just five stolen bases and 18 runs scored away from setting career highs in those categories and his .367 on-base percentage, .583 slugging and .949 OPS would also all be the best marks of his career. He leads the majors in RBIs and runs scored and is tied with teammate Mark Teixeira for second in the majors in home runs, just one behind Jose Bautista. The Yankees are only one game behind Boston for the AL East lead and hold an eight-game advantage over the Angels for the wild card. All of that, based on the voting history for the MVP Award, makes Granderson a strong candidate ... but what about his defense?

Let's be clear, Curtis Granderson has not suddenly turned into a center field version of Dick Stuart, the Red Sox first baseman known as "Dr. Strangeglove" who committed 53 errors over two seasons in 1963 and '64. In fact, in 271 chances this season, Granderson has committed only three errors. However, defensive performance these days is hardly measured on such a simplistic scale. One means of evaluation is Defensive Runs Saved, which measures the value of a player in the field by combining his ability to turn batted balls into outs with other essential skills unique to his position. Granderson's Defensive Runs Saved rating is minus-13, the worst among all qualifying major league center fielders.

As with any defensive metric, there is always a subjective element. Video scouts at Baseball Info Solutions review every batted ball and categorize plays accordingly. In this case, does the player get to balls hit to the shallowest or deepest parts of center field? Does he cover the gaps? What is the ratio of his good fielding plays and his defensive misplays and errors? How does his throwing arm prevent or allow opposing runners to advance on the bases? It all adds up to a Defensive Runs Saved number and Granderson's is the lowest in baseball at his position.

By comparison, the Tigers' Austin Jackson, the center fielder who went to Detroit from New York as part of the deal that brought Granderson to the Yankees last season, has 10 Defensive Runs Saved. Jacoby Ellsbury, the Red Sox center fielder who is another strong candidate for AL MVP, has a Defensive Runs Saved rating of plus-13, second only to the Angels' Peter Bourjos' astonishing 20 DRS. Baseball Info Solutions' research shows Granderson has been above average on balls hit to shallow center field but is struggling on medium and deep balls. It's a defensive performance that represents a startling regression considering Granderson had 14 Defensive Runs Saved in 2009 and a career-high 16 DRS in 2007.

MVP votes often turn into debates pitting the "best overall player" argument against the player "most valuable to his team" philosophy. Granderson, while having a wonderful offensive season in a ballpark that seems a perfect fit, is by far the weak defensive link in the Yankees' outfield. Nick Swisher has a Defensive Runs Saved rating of plus-8, meaning he's eight runs better then the average right fielder. Brett Gardner is a Defensive Runs Saved superstar with a rating of 18, the best in baseball in left field. Granderson's minus-13 means he has cost the Yankees 13 runs defensively. If you subscribe to the "player most valuable to his team" theory of MVP voting then defense is certainly an argument against the Yankees' center fielder.

This isn't about bashing Granderson. He's a class act and baseball needs more players like him. What is interesting here is the notion of Granderson as a test case both for the perceived value of defensive metrics around baseball and the overall value of defense to MVP voters. The offensive numbers, the ones in bold type, all scream that Curtis Granderson is a leading MVP candidate. The defensive numbers, the fine print of baseball statistics and to many the most subjective and ambiguous of all, whisper that his candidacy has flows. Lately, it seems that Granderson has been carrying the Yankees. We'll see if his statistics -- all of them -- can carry some AL MVP votes.

(Thanks to Lee Singer of ESPN's Stats & Information Group.)

Follow Steve Berthiaume on Twitter @SBerthiaumeESPN.