If you want to understand Mike Mussina's career a little better, I would strongly urge you to read this article over at THT. In it, John Brattain compares Moose and Kevin Brown (don't boo and hiss just yet). A lot of Yankees fans forget how good Brown was in his career because of the many, many lowlights of his tenure with the Yankees. Heck, the year before he joined the Yankees - 14-9 with 211 IP, 184 hits, 56 BBs, 185 Ks and a 2.39 ERA (169 ERA+ - and he didn't even get one Cy Young point...though Russ Ortiz did - weird). In any case, John puts together an interesting article comparing the steady quality of Mussina versus the insane peak of Brown - very much worth a look.

However, in the case of Mussina vs. Brown, while Brown obviously had the greater peak, who would be more deserving: Mussina with a 120 ERA+/335 RSAA/4,000 IP or Kevin Brown with 127 ERA+/304 RSAA/3,256.1 IP?
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Trouble is, their careers are somewhat similar right now, but by the time Mussina retires they most likely won’t be. There’s no comparing the two peaks; Brown was inferior to only three first-ballot inner-circle HOFers. Mussina’s peak had guys like Tom Glavine and Brown ahead of him and Curt Schilling and Kevin Appier in the general neighborhood. Not exactly chopped liver, but Mussina never had seasons like 233 IP/214 ERA+, 257 IP/160 ERA+, 230 IP/167 ERA+ and 211 IP/169 ERA+; Mussina’s sole season over 160 ERA+ came in just 176.1 IP.

Brown simply had more eye-popping seasons than Mussina. Although Brown pitched fewer postseason innings, he was the clear-cut ace of two somewhat-unlikely pennant-winning clubs while Mussina’s two pennants came after he joined a dynasty team. In the seasons in which they copped the pennant, Mussina was 34-19, 3.27 ERA in 443.1 IP while Brown was 34-15, 2.18 ERA in 494.1 IP.

I've said it before and I'll say it again - when it's all said and done, Mike Mussina should be a great candidate for the HoF. If you don't believe me, please read the linked article as well as this article by the previously mentioned Mike Green. If he can pull out a season or two like last year, even better - both for the Yankees and for his chances of induction.