Dylan Cease doesn’t have his slider

What’s going wrong with Dylan Cease? Many observers correctly predicted that he would have some difficulty duplicating the results that landed him in the Cy Young runner-up spot last year. But this kind of regression — a 4.91 ERA on the 2023 season and career-worst 8.04 mark in August — is beyond what even the most pessimistic saw coming.

Pitching is complicated, and there’s no single thing to point to in explaining Cease’s struggles. On an individual level, all of his pitches are performing worse than they have over the past few years. Walks, hits, homers, they’re all up. There’s a delicate balance of skills required to pitch at the level that he did last year, and disrupting any of them can cascade into even more issues down the line.

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We can start with Cease’s slider. In 2022, it was one of the most dominant pitches in recent memory, racking up 36 runs saved above average, by Baseball Savant’s run values. That was 11 more than Shohei Ohtani’s sweeper, in second place. It’s down to a mere 10 runs better than average in 2023, and since the start of August, its RV has been -0.3. The slider’s whiff rate has remained pristine, and on the season, it’s missed just as many bats as it did last year. But it’s easy to find problems without needing to dig much deeper.

There are the three Ls, of course: location, location, location. Nearly a full quarter of Cease’s sliders, a whopping 24.3%, have wound up in what Baseball Savant classifies as the waste zone, the areas so far off the plate that it’s more or less an auto-take for a batter. That’s one of the highest marks in the league — easily the highest of anyone who throws their slider as often as Cease does — and nearly double the 13% it was last season. That’s a lot of non-competitive pitches, and a lot of counts and outcomes are worse than if he had tempted the hitter with a swing.

Cease is not just getting burned off the plate, either. When hitters do make contact, they’re making better contact. The slider’s wOBA on contact — think of this as a kind of statcast BABIP that includes home runs — has jumped nearly 130 points, from an elite .244 in 2022 all the way up to .370 this season.

There are a number of reasons why all that could be happening. One of them is the shape of the pitch itself, because it has changed since last season. It’s not dropping quite as much, and has also lost a bit of horizontal bite, though those are both continuations of trends that existed prior to this season.

Brooks Baseball

Brooks Baseball

In other words, Cease’s slider is getting straighter and straighter. That doesn’t necessarily have to be a bad thing, and it’s far less drastic than the shift from 2021 to 2022, when his results saw a big improvement. Less movement isn’t always equivalent to a pitch that’s more hittable, either. It becomes more concerning in concert with another thing that’s seen a pretty drastic change, but this time without any precedent: Cease’s vertical release point.

Brooks Baseball

Interestingly, Cease’s horizontal release point hasn’t seen any corresponding increase, which is what you would see if he had dropped his arm slot. That can be the result of natural changes, and it can also be a consequence of fatigue and precursor to injury. No, in this case, the drop in release point comes with a two-and-a-half inch increase in extension towards the plate, aligning almost perfectly. It’s a matter of inches, so I haven’t been able to pick up much on video to support it, but it could be indicative of rotating a little too far out over his lower half before release, a slight break in his mechanics that would be consistent with more misses in the dirt.

Even all of that is still just a piece of the puzzle. The slider’s demise is bad, but so is the loss of effectiveness on his four-seamer, which has gone from an acceptable enough five runs above average (0.4 RV per 100 pitches) to eight runs below it (-0.7 RV/100) in 2023. Unlike his slider, Cease’s fastball is seeing fewer whiffs, and while it’s not getting hit all that much harder than it was last year — and is actually still doing better than it did in 2019 and 2020 — the run values indicate that opposing hitters are turning it into damage a lot more often.

Part of that is because its velocity is down a full mph from last season; while 95.5 mph is nothing to sneeze at, the unfortunate fact is that you get away with fewer mistakes at 96.5 mph than you do at 95.5 mph. At the same time, Cease is also throwing it in the zone a bit more, which isn’t necessarily great when your fastball is getting more hittable. But that’s what happens when a pitcher throws their lead pitch in the dirt a quarter of the time: They get in counts where they need to throw a fastball over to plate just to stay in an at-bat.

Kamil Krzaczynski-USA TODAY Sports

The problem is that hitters are usually waiting for those favorable-count fastballs. It’s clear that there’s something a bit different for Cease’s slider release, and that he’s not in nearly the same groove with it as he was last season. A hitter can also recognize that, and if they’re in a situation where they feel like they have to worry about that wipeout slider a little bit less, well, then they’ll be all the more excited to see that fastball.

None of this even touches Cease’s curveball, which has gotten absolutely lit up this season like nothing he’s ever thrown before. It’s only 15% of his arsenal, though, so the streak of bad batted-ball luck its seen in August is probably the least of his concerns. He’s got all of these other things to iron out. Perhaps fortunately, Cease is in no danger of needing to figure it out under the bright lights of October.

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