The recent breakdown of Boston reliever Keith Foulke, and the breakdowns in the past of closers who have had extensive work in the postseason (John Smoltz, Robb Nen, Trevor Hoffman and Mark Wohlers, etc.) further illustrates the brilliance of Mariano Rivera. This guy has been the best in baseball for over a decade and every year he pitches every day for an extra month longer than anyone else. He has essentially pitched for two full extra seasons over the past 10 years, not to mention coming on in the eighth inning in pressure games more often than not. You can argue that there has been no more valuable player in baseball, including Bonds, over the last 10 years than Rivera. -- Seth, New York City

Interesting take. Your argument gains strength when you consider he's been a huge factor on world championship teams; Bonds has not. Everyday players influence more games in more ways, but in no way can I diminish the importance of "the ultimate weapon," Rivera. What makes him so unique among closers is his year-to-year reliability, his workload (as you mentioned, pitching an extra month every year), and his efficiency with pitches and outs, which enables him to shut down games in the eighth inning as well as the ninth when the Yankees need it. On top of all that, Rivera, the man and the player, is as respected by his peers as anybody who wears a uniform. You certainly can't say that about Bonds.