Ronald Belisario, inherited runs & context

There were many reasons why the Dodgers lost 3-2 to the Angels on Thursday night in Anaheim. But the deciding run came in the sixth inning, when Ronald Belisario allowed one of two runners inherited to him by Ted Lilly to score to break the tie.

Ignoring for a moment that Belisario basically did his job, in that he got a ground ball, it continued a disturbing pattern for the right-hander this year. Over the course of the season Belisario has allowed 11 of his 17 inherited runners to score. That 64.7% rate is third worst in MLB among relievers who have inherited at least 10 runners, ahead of only Anthony Bass (11 of 13, 84.6%) and Jose Cisnero (seven of 10, 70%).

But simply counting inherited runners is too simplistic. Not all situations are created equal, with some far tougher or easier than others. Using the runs expected matrix at Baseball Prospectus, we can look at each specific situation to see the average expected runs scored in that inning, based on actual play-by-play data throughout the season.

On Thursday, for instance, the situation when Lilly left and Belisario entered was two outs, with runners on first and third base. On average, a team scores 0.4859 runs in an inning from that point forward in this situation. Belisario allowed one inherited run, but given the situation he didn't cost the team a full run, but rather .5141 of one, with Lilly responsible for the others.

Given that Belisario has been brought in 12 times this season with runners on base, I decided to look at each situation to see how much damage he has really done.

So even though Belisario has allowed 11 inherited runners to score this season, he has been put in situations that normally see about 9.6 runs score. In other words, he has been slightly below average in those situations as instead of historically bad.

The other three relief pitchers to be used often in situations with inherited runners are Paco Rodriguez, who has been brought in 14 such games, and J.P. Howell and Matt Guerrier, with nine games each. Let's look at them too.

Paco has inherited quite a bit of runners this season and has done remarkably well, over four and a half runs above average.

Howell really only had the one bad outing with runners on, though he hasn't pitched generally in as high leverage situations as Belisario or Rodriguez.

Guerrier, like Howell and Rodriguez, has been above average in preventing inherited runners from scoring, based on the situations they were brought into the game. Guerrier has been more like Howell in that he has mostly been brought into lower leverage situations than Belisario and Rodriguez on average, so make of that what you will.

Does that mean Don Mattingly should turn to Guerrier over Belisario if he needs to retire a right-handed batter in the sixth inning? Maybe, maybe not. Perhaps Paco Rodriguez could expand his repertoire even further and get used in these situations.

But the most important lesson is that it's almost never as simple as looking at inherited runners scored. Context always matters.