In light of White Sox pitcher Mark Buehrle’s perfect game, I thought I might share a little something about the likelihood of perfect games.
First of all, a perfect game is a pitching performance where the starting pitcher gets all 27 batters out in order. No walks, no hits, no hitting batters, no errors made by the defense, no runners on base for any reason. Perfection.
The best starting pitcher in the league this season at keeping runners off base is Danny Haren (I guess he goes by “Danny” officially now) of the Arizona Diamondbacks. He allows runners on base 21.8% percent of the time, and 22.8% if you count errors. On an average day for Haren this season, the likelihood of him getting ONE out is about 77%. 27 straight outs? 0.09%. As well as he’s pitching this year, Haren has a 1/1,000 chance of pitching a perfect game.
The league average pitcher has 1/75,000 odds, Mark Buehrle had 1/22,000 odds, and the great Jeff Suppan? 1/625,000 odds.