Another stat for Rivera to dominate

As if you needed more evidence that Mariano Rivera is the best closer in baseball, we did a little statistical study earlier this morning, the hook being that Joakim Soria converted his 27th straight save opportunity last night -- the best current streak in baseball.

Only seven pitchers have 100 saves since the beginning of the 2008 season. Among those seven closers, only two have had a save percentage of better than 90 percent: Soria and Rivera.

Pitchers with 100+ Saves Since 2008

Highest Save Percentage

Taking that same collection of seven closers, let’s examine who has been the most dominant en route to recording these saves. We’ve created an attempt to measure the dominance of a closer by creating what we call the “Game Over Index.”

The "Game Over Index" measures the percentage of the time a closer records a save without allowing any runners to reach base. Divide the number of those saves by the pitcher’s amount of save opportunities, and you get Game Over Save Percentage, or their “Go Saves” number.

Highest Game Over Index

100+ Saves (since 2008)

To the surprise of no one, Rivera tops that list, too. Nearly 50 percent of Rivera’s 112 regular season saves since the beginning of 2008 have been of the ‘game over’ variety, the only pitcher during that time span to get close to pulling this off half of the time. Soria is once again second, at 43.0 percent, just ahead of Jonathan Papelbon.

Let’s look at this season on its own. Once again, ‘The Great Mariano’ is on top of the list, at nearly 60 percent. Rivera has had 26 save opportunities in 2010, and 15 times he has recorded a save without allowing a runner to reach base. The only two other pitchers in baseball to post a Game Over Index of greater than 50 percent are David Aardsma of the Mariners and Neftali Feliz in Texas.

Highest Game Over Index

Players with 20+ Saves (2010)

So no matter how you slice the numbers, Rivera is still the best closer in baseball. While Soria’s stretch of 27 straight saves is impressive, and he’s a dominant weapon in Kansas City, the best man to seal games still plays in pinstripes.