Rivera turned 40 in November. Pitchers usually slow down at this point, but apparently no one bothered to tell this to Rivera.
How does he do it, year after year, though? While he is not a bad strikeout pitcher, with a career 8.30 K/9, he has not topped 10 K/9 since 1996, which was his first full year out of the pen (and where he survived Joe Torre's vendetta against setup men, pitching 61 times for 107.2 innings). Rivera has been the closer since, and it has been miserable for a Red Sox fan.
Do finesse pitchers not usually flame-out quicker than power pitchers, though? I thought so too, and it is usually the case, as you can teach finesse, but not power. But when you let fewer than 0.5 balls per nine innings clear the fence over a near-1,100 inning career, something is being done right.
Rivera has not posted a FIP over 3.00 since 2000. That is an incredible feat. The No. 1 spot in the AL is his to lose, especially with Nathan on the shelf for 2010.