In 2022, Jordan Hicks briefly converted from relieving to starting for the Cardinals. The experiment didn’t go particularly well. He made eight starts and lasted a combined 26.1 innings with an ERA of 5.47. He walked nearly 20% of the batters he faced, barely struck anyone out, and seemed to struggle to adjust from his old role. He threw sinkers or sliders 94% of the time, didn’t dial down his velocity much, and looked exactly how you’d expect a closer cosplaying as a starter to look. So much for that experiment; he promptly returned to late-inning duty.

When the Giants signed Hicks this offseason, rumors of his return to the starting ranks bubbled up, but I didn’t believe it. After all, we’d already seen this exact experiment before. But fast forward to today, and Hicks looks like a revelation. Through two starts, he’s thrown 12 innings and allowed a single earned run. His strikeout rate has barely budged from his career average, and he’s only issued two free bases (one walk, one HBP). It’s a remarkable turnaround, and one that I can’t help but dive into. How has he done it?

The most striking change to Hicks’ arsenal is his new sinker. He was one of the hardest-throwing pitchers in baseball history as a reliever. This year, 19 different starters are throwing harder than he is. Take a look at how different this new pitch is compared to both his sinker from last year and from the last time he started in the majors:

By dropping his release point and throwing more slowly, Hicks has created more horizontal movement. The result makes for some pretty GIFs, and also some befuddled takes from hitters:

I know what you’re thinking. It’s not like Hicks particularly needed more movement. His biggest issue in the past has been throwing strikes. But even with more movement, Hicks is commanding his sinker in the strike zone far better in 2024 than he did earlier in his career:

That’s a lot of numbers, but the gist is easy to understand: more pitches in the strike zone, more swings, and far fewer balls per sinker thrown than before. That’s how you end up with fewer walks, but it also means more pitches thrown in pitcher’s counts, more opponents on their heels, and a whopping three fewer pitches per inning than Hicks averaged last year. That matters a ton; assuming a roughly static per-game pitch count, Hicks could finish roughly an extra inning per game if he keeps up his current rates.

Of course, it’s not quite as simple as that. Part of the reason for his low pitch count is that he’s allowing a .250 BABIP, and that won’t hold up. Another part of the explanation is that opponents are swinging at sinkers out of the strike zone at an unsustainable rate. That 40% mark is going to come down; only one pitcher who threw 200 sinkers last year topped 40%.

It’s not all unsustainable improvement, to be clear. It’s a lot easier to make opposing batters swing when your pitches are close to the edges of the zone, but in his career, Hicks has missed by a lot fairly often. In his career before this year, he threw 26.4% of his sinkers in the “chase” or “waste” zones as defined by Baseball Savant. Opposing batters swung at only 13.2% of those pitches – they’re just too far away to fool anyone. In 2024, batters are swinging at 17.6% of Hicks’ sinkers in those zones, which isn’t much different. Far more importantly, though, he’s throwing far fewer of those pitches. His chase and waste rate is down to 18%. Fewer uncompetitive pitches means better outcomes, in other words.

That’s only part of what’s going on with Hicks, though. From a pure stuff standpoint, this year’s version of the sinker is worse. But he never missed a ton of bats, even when he was sitting above 100 mph, because of the shape of the pitch. By throwing it slower, he’s gained enough in command to more than offset what he lost in raw velocity. Both of our pitching models think that Hicks’ sinker is just as good overall as it was last year, which is an incredible coup for someone stretching out from single-inning stints to starting.

Of course, Hicks’ job is a bit more complex than just throwing sinkers all day and checking the pitch metrics afterwards. In fact, by the time Hicks reached free agency, his sinker was a less important pitch than his slider. It’s taken on an increasingly sweeping shape in recent years, and it was his go-to out pitch in 2023, with an impressive 20.4% swinging strike rate. He hasn’t missed bats with quite the same frequency this year, which makes sense. After all, he’s throwing the pitch four ticks slower with roughly the same shape.

That hurts Hicks against righties, but the truth is, he’s never needed much help there. Even a diminished version of his slider is enough, particularly when he’s spotting his sinker as well as he has been this year. High octane sinker/slider guys just don’t have trouble with same-handed batters. His career .247 wOBA allowed to righties says one thing: Good luck, buddy. Meanwhile, lefties have frequently gotten the better of him. That’s because sinkers and sweepers both work a lot worse without the platoon advantage.

In seasons past, Hicks has tried a few different things to handle lefties. He dabbled with a changeup for years, never throwing it more than 5% of the time. He tried a cutter one year, and he’s occasionally taken a ton of velocity off of his slider and tried to throw it like a curveball. None of these things have worked. Lefties rarely strike out against him, walk quite frequently, and hit the ball on the ground far less frequently than righties do. Grounders are Hicks’ great equalizer; without them, he doesn’t strike out enough batters to outpace all the walks he generally issues. Lefties have posted a .326 wOBA against him, better than league average for all hitters.

The answer was obvious in retrospect: throw the new hotness. Hicks has a splitter, and it looks like a good one to me. It’s a classic version of the pitch, without a ton of induced break in any direction. He just kills the spin with his grip and lets gravity do the work:

The splitter works against righties, but the real reason he’s added it is for lefties. Jackson Merrill is the exact kind of hitter who would have given Hicks fits in the past, but this is one of two strikeouts (in four plate appearances) Hicks has recorded against him using a splitter this year:

He’s throwing the split 20% of the time against lefties so far this season. With two strikes, he’s thrown seven times out of 19 pitches, 36.8%. That takes pressure off of the rest of his game, because converting two-strike counts into outs against lefties has long been a big weakness. Now it’s more of a fair fight, because the old wait-and-foul plan doesn’t work well against that splitter.

Now, lefties are still killing Hicks this year, to the tune of a .313/.389/.375 line. But that boils down to a ridiculous .500 BABIP allowed, and that won’t continue. He has six strikeouts against lefties already, as compared to one walk and one HBP. In his entire career before this year, 19% of his two-strike pitches to lefties ended in a strikeout. This year, that number has ballooned to 31.6% in a tiny sample. The league average for starters is 18.6%.

I don’t think Hicks will keep his strikeout rate nearly so high against lefties; we’re just looking at a small sample for now. On the other hand, he’ll probably start striking out more righties in two-strike counts. He’s at a piddling 15.6% putaway rate (two-strike pitches that turn into strikeouts) against righties so far in 2024, as compared to 24.7% in his career so far. With his slider and sinker, I’m confident that he should be at least league average there, so he’ll get back plenty of the strikeouts he’s missing against lefties when facing his natural prey, right-handers.

This almost sounds too easy. How did Hicks turn into a great starter? By changing his sinker shape to suit his diminished velocity, going from scattershot to pinpoint accuracy, and adding a new pitch out of nowhere. Oh, sure, simple! Everyone should do those things.

In reality, it’s unlikely that Hicks will keep cruising to the extent he has so far. He’s going to have a game where the command doesn’t come easily. He’ll have a few calls go against him and have to fight back, or lose command of the splitter briefly and have to come up with a new plan against lefties. Righties won’t keep batting .136 on balls in play against him, just as surely as lefties won’t keep batting .500. But overall, I think Hicks has done what I didn’t think was possible: turn himself from a wild reliever into an acceptable starter in a single offseason. I’m incredibly impressed, and I look forward to seeing more of his new form the rest of the year.