I can tell you with certainty that he is not. Being a former closer, I can tell you that the games you save are not the important ones; it's the games you blow.
When you're saving games, things seem easy. You're getting strikeouts, and your fielders are making plays on hard-hit balls.
Looking at what has gone wrong for Rivera over the past week or so, I see with ease what has happened. On a couple occasions, his cutter backed up on him and was hit out of the park. But his mental approach is what's made him the best closer in the history of the game.
Rivera said it himself: "This won't make me or break me."
His ability to put yesterday behind him is what makes him the best. Rivera has had stretches in the past where he has struggled, but he always found a way to come back and be Mariano. He began Tuesday having converted 31 of 36 save opportunities this year, posting a 2.35 ERA. There are closers who aspire to those numbers.
Despite his so-called struggles, Rivera has joined Trevor Hoffman as the only players in Major League history to have nine consecutive seasons with 30 or more saves. Rivera has posted an ERA under 2.00 10 times during his 17-year career.
So if you're worried about Mo, don't be. He has set the bar so high for himself that perfection is the expectation. Rivera going to be just fine. And if Yankees fans don't think he will be, I'm positive fans of 29 other teams would love to have him.
Rivera is a 12-time All-Star, a five-time Rolaids Relief Man Award winner and a five-time World Series champion, not to mention Most Valuable Player of the 2003 American League Championship Series and the World Series in 1999.
Regardless, what makes Rivera the greatest closer in MLB history -- and not Hoffman, despite more career saves -- is this: If the Yankees make the postseason, they will do so with a closer who has 42 postseason saves in 46 opportunities. Add to that the fact he is 8-1 with a 0.71 ERA in the postseason. That is what makes him the best.
The man knows how to adjust, and he will adjust again.
Mitch Williams is an analyst for MLB Network. This story was not subject to the approval of Major League Baseball or its clubs.