When someone asks who is one of baseball’s best closers, Mariano Rivera is among the first names on that list, and rightfully so. His career ERA is in the top 15 all time, and his ERA-plus is easily the greatest all time, not to mention his save numbers, and World Series rings as a member of the New York Yankees.

So what’s left for this dominant relief pitcher to accomplish at 40? How about holding a 0.00 ERA as long as he did.

After Minnesota Twins slugger Jason Kubel’s grand slam on Sunday off Rivera tabbed him with the loss, he was the second-to-last reliever  to lose his perfect ERA to start the season, losing only to Baltimore’s Will Ohman.

This is the third time Rivera has kept a perfect ERA until mid-May. In 1998, he lost it on May 14 against the Texas Rangers, his 11th game, and in 2008, he lost it on May 13, his 15th game, against the Tampa Bay Rays. Then today, in his 13th relief appearance, he given up his first earned runs of the season.

That being said, he had never gotten as far as May 16 with a perfect year intact, and this just shows how phenomenal a pitcher that he is. Pitchers occasionally make it this far on a fluke once, but they don’t three times unless they are just that good.

As there is no need to make this a long speech about how good he is, since most folks already know that, so let’s just look at a few facts both interesting and somewhat random from Rivera’s performance this season in comparison to his previous ones.

First, in 1998 and 2008, the two teams he lost his perfect ERA to won their division. It looks like it will be 3-for-3 with Minnesota taking the Central.

Second, even after that, his current ERA of 1.59 is the best of his career. This asks the question, how far could he go? Could he play until he’s 45? He’s clearly as dominant as he’s always been, so that’s a possibility.

Third, his WHIP of 0.617 is the best of his career. Not only that, but WHIPs like that just don’t exist in baseball statistics. That’s how good it is. All-time leader Addie Joss’s best was .806, and Ed Walsh, second all-time, and just ahead of Rivera in WHIP, had his best at .820. Rivera, meanwhile, has a previous best of .665.

What I’m trying to explain is simple. Even with his illustrious career, Rivera is still on pace for a personal best season, as well as an all-time great relief season.

There’s really nothing to compare his performances to, given that amazing pitching seasons are still inherently kept in the camp of starting pitchers.

If Andy Pettite or Phil Hughes were to slump away, could this be the year that Rivera wins a Cy Young? He’s certainly deserving of one, and that really is the one crown jewel missing from his career.

Rambling aside, I leave the questions to you: If he keeps this up, should he get the Cy Young Award this season? How about his Hall Of Fame credentials, has he shown enough to get in on the first ballot

Or will the bias against relievers keep him away for a couple years?

Sure, it’s May 2010, but with Mariano Rivera, we know he’s going to be great (we can write 2007 off as an off year by now), so it’s not too early to think of this.

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