Patrick Corbin finding his stride — and slider — on the bump for Nationals

Since winning Game 7 of the 2019 World Series, Patrick Corbin hasn’t been the same.

In 59 starts over the past two-and-a-half seasons, the Nationals’ lefty has a 15-33 record with a 5.55 earned run average. Those numbers, on top of his diminished strikeout rate as well as burgeoning hit and home run rates, make Corbin one of baseball’s least effective starting pitchers since 2020. 

But unlike teammate Stephen Strasburg, who also hasn’t been the same since 2019 when he was the World Series MVP award, Corbin’s issues aren’t health-related. He took the mound 31 times last season — including an MLB-worst 16 losses — and he’s leading the National League in games started this season with 17. Like Strasburg, though, Corbin is making an exorbitant amount of money at $23 million per season, thanks to the six-year, $140 million deal he inked with Washington after his All-Star campaign with Arizona in 2018.

However, over the past few weeks, Corbin has started to look a little bit more like the version of himself that earned Cy Young votes in 2018 and 2019. Over his past six starts, Corbin is 3-2 with a 3.67 ERA and 31 strikeouts in 34 2/3 innings. He’s been even more dominant in his last two outings. He punched out 12 batters in eight innings of one-run ball against the Pirates last week and followed that up Sunday with a seven-inning, one-run start against the Marlins. 

His ERA, which was at 6.96 after his dreadful start against the Mets on May 31, has fallen to an improved — but still underwhelming — 5.68. 

“I’ve felt good even before this,” Corbin said when asked if he feels like he’s hitting his stride. “I more so look at how the ball’s coming out, how my pitches are moving more than I look at the results. Obviously, you want results, but sometimes it doesn’t happen.”

For Corbin, the key to success has always been his slider. Once one of the most devastating pitches from a left-handed starter in the major leagues, Corbin’s slider doesn’t have the same bite as it did when he posted 14 wins and a 3.25 ERA in his first season with the Nationals in 2019. 

That season, Corbin garnered a staggering 51.4% whiff rate on his slider — meaning more than half the time batters swung at the pitch, they missed. Overall, hitters compiled a .158 batting average and a .266 slugging percentage against Corbin’s slider in 2019. But in the years since, those numbers have all steadily worsened. Now, batters are hitting .275 off Corbin’s slider with a .492 slugging percentage, and his whiff rate is down to 36.7%. 

One potential reason for the decline in his slider’s effectiveness is its spin rate. Once nearly 2,400 revolutions per minute, Corbin’s slider is now at 2,189 rpm. However, in Corbin’s recent starts, his spin rate on his slider has improved, registering above 2,200 in each of his past five starts. 

“I think the break has been more consistent,” Corbin said. “I know that’s my pitch, and I’ve got to throw it. It’s been good.”

Additionally, the velocity on his slider has increased. His average slider Sunday versus the Marlins was 83.2 mph, with a max velocity of 85.5 mph. Against the Pirates, when he got 14 whiffs on 19 swings against his slider, the pitch was 81.9 mph with a max velocity of 85.9 mph. For comparison, Corbin’s slider in 2021 was 80.7 mph and 79.2 mph in 2020. A faster slider, combined with an improved spin rate, could make for a challenging combo for opposing hitters.

“He’s been attacking the strike zone, and I’ve talked a lot about his slider,” Martinez said. “He’s actually throwing his slider a little harder, and it looks like his fastball coming in. It’s been very effective.”

Of course, it’s not just about his slider’s spin rate and velocity. His pitch selection and command — of his slider as well as his four-seam fastball and sinker — are just as important if Corbin is going to get anywhere close to where he was in 2019. The 32-year-old southpaw may never again be a pitcher worth $23 million or worthy of Cy Young votes, but that doesn’t mean he can’t be a valuable asset to the Nationals’ rotation as he’s been since the start of June. 

“He’s been one of the guys since he’s been here, and I’ve always felt that way no matter what kind of outing he has,” Martinez said Sunday. “Without him, we wouldn’t have done what we did in ’19. I know he’s struggled, but I really believe that he’s got the stuff to continue to be really good and you saw it today.”