Posted by Bill Baer on Monday, June 29, 2009 at 10:09 am

Cutter after cutter, strikeout after strikeout, save after save. 500 of them in 561 opportunities (89%) over 15 Hall of Fame-caliber seasons. They say there are no sure things in life, but the New York Yankees found the closest thing when they put Mariano Rivera in a save situation on May 17, 1996 against the California Angels. He earned his first ever Major League save. A star was born.

Rivera is on just about every statistical leaderboard out there. Career K/BB rate, all-time? Fourth. WHIP? Third. ERA? 18th (the next-closest active player is Trevor Hoffman at 91). According to FanGraphs, Rivera has been the most valuable reliever in all of baseball twice in the last four seasons and has always been in the top-ten as far back as FanGraphs has accumulated value statistics, 2003.

In an era where relievers are shuffled more than the Queen of Hearts in three-card monte, Rivera has been there to nail down Yankee leads, no matter how slim the margin or how tense the situation. Since Rivera established himself as a closer, the Yankees have never once considered removing him from that role for any reason. Very few closers can say that they’ve had job security that comfortable. That’s what happens, though, when you hold opponents to a .559 OPS.

As yet another illustration of just how great Rivera is, consider Brad Lidge’s season was last year. It was perfect: he was 41-for-41 in save opportunities with a 1.95 ERA. Would you believe that, according to FanGraphs, Rivera was worth nearly a full win more than Lidge? It’s true.

Oh, and did I mention that he’s a nine-time All-Star, has finished second once and third thrice in Cy Young voting, and has helped the Yankees win four World Series championships? Rivera is, bar none, the best reliever ever to pitch in the post-season. In over 117 innings, he has a 0.77 ERA in post-season play.

Rivera’s value has helped the Yankees in other ways, however. Think of the deals handed out to premier closers in recent years: Lidge 3/$37.5M, K-Rod 3/$37M, Joe Nathan 4/$47M, Francisco Cordero 4/$46M. For as rich as the Yankees are, they still wouldn’t have had the flexibility to go after players like C.C. Sabathia and Mark Teixeira if they had to worry about fixing the back of their bullpen. Think the Mets would have lost the NL East the past two seasons if they had even one-fourth of the reliability the Yankees have had with Rivera?

Every so often, a player comes along and transcends his contemporaries, instead finding himself in the same conversation with baseball’s all-time greats — and Rivera is a reliever! If Barry Bonds is the greatest modern hitter, Rivera is arguably the greatest modern pitcher, or at least the greatest modern reliever (move over, Eckersley). Even more impressive is that he’s built his success entirely on one pitch: the cut fastball.

What does his cutter look like? Thanks to Harry Pavlidis of Cubs F/X and Beyond the Box Score, we can insert Pitch F/X data into a template he’s created and made available for the masses. I took two of Rivera’s cutters he threw last night (the strikeout pitches to Omir Santos and Jeremy Reed) and compared it to a Zack Greinke fastball, so we can make judgments about movement. Click the images for a larger version.

First base view:

Birds-eye view:

That’s the bread-and-butter that Rivera has used to repeatedly dominate American League hitters since 1997. Imagine having to face a Zack Greinke fastball that’s just a couple MPH slower on average, but with tremendous movement towards the left-handed batter’s box. Oh, and if you happen to make contact with it, not only does your bat have a high probability of being splintered, but the pain in your hands will tell you that you just swung at a bowling ball.

In fact, Rivera’s cutter is so feared that switch-hitters will hit right-handed against him because of how often the cutter will jam lefties. Chipper Jones once called it a “buzzsaw.”

While he may not be liked by his fiercest division rivals, Rivera is at least highly-respected:

That’s pretty amazing,” said Red Sox closer Jonathan Papelbon, whose 130 career saves represent barely more than a quarter of Rivera’s total. “The biggest thing that amazes me is that he’s done it with a consistency that’s pretty much unheard of. He’s really never had a down year. — Jonathan Papelbon

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That’s a huge accomplishment,” said Red Sox second baseman Dustin Pedroia, who — despite being an MVP — hasn’t recorded a hit off Rivera in six career at-bats. “He’s been the best for a long time. I think everyone respects him and is happy for him, and he’s a first-ballot Hall of Famer. Everyone knows how great he is. When he comes in for that ninth inning, you know it’s going to be a battle. — Dustin Pedroia