What Are The Odds: Bobby Jenks

As you have likely heard, White Sox closer Bobby Jenks has retired all 41 batters he's faced over the last 13 appearances. Obviously this is a very impressive streak, and quite rare, as he has tied the ML record held by the immortal Jim Barr. But just how unusual is it for a player of Jenks' ability to put together such a streak?

On July 18, the day before the streak started, Jenks had pitched 39.1 innings, striking out 36 while allowing 35 hits and walking 12. His ERA was 3.89, and he had allowed a line of .246/.299/.324. The OBP of .299 is what we'll use.

Allowing an OBP of .299 means the chance of Jenks getting any random hitter is 70.1%. Given that information, here's the chances of him going on streaks of various lengths.

So, essentially, it's quite unlikely. To be fair, these are the odds that he will retire this many consecutive batters in any single stretch of this number of games. According to FanGraphs, Jenks has faced 198 batter so far this season. Here are the numbers for him accomplishing these streaks at least once throughout the year.

Still unlikely, but much more reasonable.

So, what are the chances he extends this streak beyond 41? His OBP allowed is now all the way down to .241, so for the purposes of this exercise I'll use that.

The White Sox begin a three game series with Oakland on Tuesday.

Stats taken from Baseball Reference and FanGraphs. Pictures taken from here and here.