Patrick Corbin’s command is sliding away

After Patrick Corbin put up a career best season in which he pitched to a 3.15 ERA, a 2.74 DRA and a 5.9 fWAR, it’d be reasonable to think that biggest pitching prize of the offseason might take a step back. He was effectively twice as good as he had ever been in a full year, but Corbin made some real improvements in 2018. His increased slider usage was widely documented, and as long as he continued to throw one of the best breaking balls in the game most of the time, he should have carried his success into 2019 and beyond.

Through the middle of June, Corbin finds himself with an ERA of 4.11. FIP and SIERA both put him a smidge under 4.00, though DRA has him at 3.27. His strikeout rate has dipped but it’s still above pre-2018 levels. Overall, it looks like he’s taken the step back that we might have expected from him, but his performance of late has been concerning.

In his last three starts, Corbin has thrown just 12 2/3 innings while allowing 20 runs. In his most recent outing, he gave up seven earned runs in five innings, the most he’s allowed in any start since September 8, 2017. This has been his worst five-game stretch in the last two years, which is impressive considering he had a complete game shutout mixed into those five games.

FanGraphs

Corbin primarily throws his slider, but he also throws a sinker as well as a four-seam fastball. The slider, which has been so deadly, is rarely thrown for a strike if the batter is taking. Even in his wildly successful 2018 campaign, he only threw his slider in the zone around a quarter of the time. Because of this, Corbin typically throws his slider when he’s ahead in the count. To do that, he needs to get ahead with a fastball.

Baseball Savant

By Corbin’s own admission, his fastball command hasn’t been there. The sinker hasn’t been any worse in getting strikes this year, but he still throws it over the plate less than half the time. His four-seamer has been all over the place. Last season, Corbin threw 58.1 percent of his fastballs in the zone, but in 2019, that’s down to 50.2 percent. Because of his wavering fastball location, Corbin is getting first pitch strikes less often and he’s falling behind more than usual. If he’s behind, he can’t use his best weapon as much as he needs to be successful.

Corbin’s command problems also haven’t been helped by the catchers framing his pitches. Corbin is now throwing to Kurt Suzuki and Yan Gomes this year rather than Jeff Mathis, John Ryan Murphy, and Alex Avila. Both Gomes and Suzuki have been below average this year at framing pitches.

In light of his command issues and his less effective framers, it’s perhaps good news that Corbin’s walk rate hasn’t risen more than it has. His walk rate is at its highest since 2016, but an 8.2 percent mark isn’t that concerning.

Corbin’s on the skids right now, but his slider is still exceptional. As long as he can get back to throwing first pitch strikes and putting the fastball where he wants it, he can still tear through hitters. If the Nationals are going to turn their season around, they’re going to need Corbin to do that.

Kenny Kelly is a writer for Beyond the Box Score and McCovey Chronicles. You can follow him on Twitter @KennyKellyWords.