Matt Cain’s struggles with runners on base

Matt Cain is currently working on his second consecutive down season, leaving a lot of fans and analysts to wonder what has happened to him. He got shelled Monday night by the Padres, a team whose offense wouldn’t even advance in the College World Series, much less against the ace of San Francisco. The plot thickened. Then Giants’ beat writer Henry Schulman clued me into an interesting little factoid.

This seems plausible. After all, Cain is stranding the lowest number of baserunners in his career, only 67.6%, about five percentage points under league average. And then his splits jump out as well, with opposing hitters grinding him to the tune of a .374 wOBA with men on, and only a .300 wOBA with the bases empty. There’s clearly something here, but we have to separate all the noise away from the real cause.

The first part is understanding baserunner splits. Of course more runs score when there’s men on, that’s common knowledge. Hitters do perform better as well, with a wOBA of .316 with men on compared to only .311 with the bases empty. Even home run ratios go up slightly with runners on board. So Cain’s struggles aren’t new to any pitcher. The troubling thing about his splits is how big they are. Cain’s 74 point increase in wOBA with runners on is one of the largest leaps in baseball, and a driving factor behind his bloated 4.52 ERA and 5.02 FIP.

To really get down to the core of the issue, let’s compare his different mechanics out of the windup and the stretch:

Cain’s windup

Cain’s stretch

The mechanics don’t seem to be any more complex from the stretch, just a lot quicker. But therein lies the problem, as pointed out by Schulman. Cain is sacrificing his control with runners on to be quicker to the plate. He’s always among the league leaders in stolen bases allowed, and he’s shortened up his stretch to cut down on those.

Look closely and compare both gifs, and it’s not hard to see the issue. Cain’s quickness is costing him his excellent posture that he has in the windup, and is causing him to yank the ball down and away (from a right-hander’s perspective). His heat map with runners on backs up what the eye test is telling us.

This map is from the catcher’s view. There is a some random variation in it, as with all heat maps, but there’s a large cluster on the outside third, away from righties. Hitters are able to pick up his patterns because he’s pulling the ball glove-side, and those are the kind of tendencies that get you in to trouble quick. To add to his pains out of the stretch, hitters are also being more patient, laying off more pitches to make Cain come to them. His 9.4% walk rate with runners on is two full points higher than with no runners on, at 7.4%.

For someone with such glaring issues, it would be expected Cain is doing everything he can to avoid giving up a baserunner. Yet his walk rate is his highest since 2008, at 9.0%, and he’s throwing less strikes, going from 50.7% last year to 47.4% in 2014. He’s getting ahead of hitters less often, as his first strike rate has dropped from 63.3% to 60.7% and he’s striking out a career low at 18.4%. Cain is making it easier on hitters to walk against him, and they’re taking advantage. Without his strikeout ability in his back pocket, Cain is just making it too hard for himself to get out of jams.

It looks like Matt Cain made a decision to cut down on stolen bases by changing his mechanics. The trade-off was that he can’t get out of an inning when hitters get on, and he’s suffering; he currently is worth -0.4 RA9-WAR and fWAR. If Cain had just looked up the numbers, he would have realized he never needed to cut down on stolen bases. Opposing base runners have stolen successfully against him 69% of the time, which is well below the  break-even point of 70-75%. Even though he’s top ten in steals against, opposing teams are hurting themselves more often because of their poor success rates. Had he not made his mechanical tweak, and sacrificed his ability to pitch out of the stretch, there’s enough evidence to believe we would have never seen this side of Matt Cain.