Why is Rick Porcello giving up so many hits?

Everyone expected some regression from Rick Porcello in 2017. It’s not that he’s a bad pitcher — not even close — but everything went perfectly for the right hander en route to his Cy Young award last season. It was essentially impossible to expect more of the same for him in 2017. A few more hits were going to fall in and a few more balls would fall on the other side of the fence. At least, that was what we thought.

As the season has gone on, at first glance it seems as if the regression has gone too far. With Drew Pomeranz turning his season around and David Price putting up an encouraging first outing back from the disabled list, Porcello is trending worse than any other pitcher in the Red Sox rotation. That’s not to say he’s not going to get better, but there’s one portion of his game that needs to get better before he can improve. Simply put, he’s giving up far too many hits.

After giving up eleven hits in each of his last two outings, Porcello is allowing 11.6 hits per nine innings this season and is averaging 1.5 base runners per inning. That is not a good rate for sustainable success, and it’s led to a 4.21 ERA despite a solid 3.57 FIP that is only slightly worse than last year’s mark. The main culprit, of course, is the .370 batting average on balls in play that Porcello has allowed this season. It’s easy to call that number bad luck, and to be sure luck plays a factor in that number. You can’t allow a BABIP that high without some luck being involved. Poor defense, particularly in the infield, also plays a major role.

It’s not just that, though. Porcello is responsible for some of his own bad fortune, and the more you look the more you see why. Really, it’s a simple issue that he needs to correct: He’s allowing too much hard contact. We’ll dig into the reasons for the hard contact, but that’s what it all comes down to. According to Fangraphs, the reigning Cy Young award winner is allowing hard contact over 42 percent of the time, the second-highest rate among all qualified starters in baseball. As I pointed out earlier this year, Porcello is allowing more balls in the air this year than ever before. This is fine, but when the ball is being hit this hard it’s obviously a recipe for disaster.

The issue for Porcello is pretty simple: A sudden lack of command. The righty is catching too much of the plate on a regular basis. His superb control hasn’t left him this year, as he’s still walking fewer than two batters per nine innings, but he’s catching the fat part of the plate far too often. Below are two zone plots courtesy of Fangraphs. The first is from last year and the second is from this year.

As you can see from the plots above, there is a lot more dark red in the middle part of the strike zone this season than there was last season. Porcello’s ability to work on the edges of the strike zone was part of the reason he was so successful in 2016. In a way, he created his own luck. It hasn’t been the case this year, and it’s showing in his numbers. In particular, he hasn’t been working to his arm side in 2017. There’s a whole lot of blue on that side of the plate, and it goes without saying that it’s hard to succeed if you’re avoiding an entire side of the plate.

Looking at Brooks Baseball, the biggest problem for Porcello appears to be his curveball, a pitch that he has thrown more often this year than he did in 2016. Opponents have been able to connect on line drives against the pitch at twice the rate they did a year ago and it’s also producing the lowest whiff rate among any of his offerings. Sure enough, if you look at the zone plot of just his curveballs, you’ll notice that a good chunk of them have been hung right in the middle of the zone, and he hasn’t been able to place the pitch to his arm side.

So, there are changes that need to come for Porcello if he’s going to start allowing fewer hits. At some point, he’ll start to get better luck and hopefully the defense behind him will do the righty more favors, but Porcello has his own work to do. As he takes the mound on Friday night in Baltimore, look for him to work the edges of the zone more, particularly to his arm side. If he can do that, while possible ditching that curveball, we could see a much more successful Rick Porcello.