Luis’s Lost Whiffs

Yesterday was another clunker of a start for Yankees’ ace Luis Severino, making it two disaster starts in a row, following a not so great one against Cleveland and a meh-at-best one against the Blue Jays. On the plus side, he only gave up one home run against the Royals yesterday, after surrendering at two apiece in his last three starts prior. Another plus? He’s mostly kept the walks down while maintaining a high strikeout rate–except against Cleveland. Regardless, his performance in July was nothing like his performance in April through June, so what gives? The answer, my friends, is blowing in the wind that Severino’s pitches aren’t generating lately.

From the beginning of the season through his July 1 start against Boston, Severino’s (excellent) fastball netted him a whiff/swing% of 23.04. The changeup? 24.27. Slider? 37.82. Those are all solid marks befitting a hurler with the kind of stuff Severino has. But since then, through yesterday, all of those numbers have seen marked dropoffs.

In that time frame, Severino’s fastball whiff/swing% is all the way down to 14.29. His changeup’s whiff/swing% is down to a shockingly low 8.33%. The slider’s drop off to 33.33 isn’t alarming or overly big, but a drop is a drop. Not surprisingly, this has led to an increase in balls in play on his fastball, from 15.39 to 21.28. On all three pitches, his fly ball and line drive percentages have climbed, also leading to increases in HR/(FB+LD) rates on his fastball and slider. On his slider and changeup both, the ground ball percentages have dropped by about 5% each.

With regards to the fastball and its drop in whiffs, a big culprit seems to be that hitters against Severino aren’t swinging through fastballs in the zone like they were before. Now, especially in that top part of the zone, hitters are whiffing less. It’s not a velocity issue, as he’s still averaging in the high 90’s. Perhaps, then, it’s a sequencing issue or hitters are reading the ball out of his hand better. Another sign of that is the increase in swing rate on his fastball and the paired decrease in swing rate on his changeup.

Up through the Boston start, hitters swung at about half of Severino’s fastball–50.94%. In his last four starts, that number has crept up towards two-thirds–64.54. The swing rate on his changeup has gone from 44.40 to 34.29. This hints towards better pitch recognition on the hitters’ part or weaker deception on Severino’s part. Either way, it’s leading to issues and there needs to be a correction made.

This is only four starts in an otherwise brilliant season, but with the Yankees trying to chase down the seemingly indomitable Red Sox, each game matters. If I told you yesterday the Yankees would score five runs in a Luis Severino start, you’d think that was a win no matter what. It didn’t shake out that way and hasn’t for most of July. Hopefully August brings better returns for the Yankees’ ace.