Yesterday, on our three hour ride back from the postponed Scranton AAA doubleheader, my friend Brent and I got into an argument about Alfredo Aceves.
I maintained that the best comparison for what he's done this season is Ramiro Mendoza. Brent suggested the 1996 version of Mariano Rivera. As you might have imagined, I laughed it off completely.
Then Brent got me the stats:
In 1996, Mariano had a 2.06 ERA. A WHIP of .994, 6.1 h/9, an ERA+ of 239 (!!!) 2.8 walks per nine, 10.9 K's per nine and 3.82 K/BB. Rivera stats
In 2009, Aceves has an ERA of 2.02, a WHIP of .925, 6.8 h/9, an ERA+ of 216 (!!), 1.6 walks per nine, 7.7 K's per nine and 4.86 K/BB. Aceves stats
Now, there is of course the caveat that Aceves' 40 innings pitched do not equal Rivera's 100+ innings pitched, but at the halfway point of the season the 40 IP is not a horrendously small sample size.
Of course, the major difference between Rivera and Aceves is that Rivera is, well, Mariano Rivera, with the cutter that is a gift from God, but he didn't develop the cutter until 1997, while playing catch with Ramiro Mendoza (you see, in baseball things come full circle).
So in 1996 Rivera had yet to discover the pitch that would set him apart, and yet many who remember would say Rivera was an invaluable resource as to why the Yankees won that world series.
Now look at 2009 and what Aceves is doing—outperforming Rivera (even if only by a little) in ERA, WHIP, BB/9 and K/BB.
Aceves won't turn into Rivera, because what Rivera has done over his career is unmatchable, unless Rivera wants to teach Aceves that cutter, but...
...I don't know what the Yankees expected when they signed Aceves.
I don't think it was this.