Pittsburgh Pirates: Four Noteworthy Underlying 2022 Stats

Ji-Man Choi – .415 wOBA Without The Shift

wOBA, or weight on-base average, is a more advanced version of slugging percentage and OPS. It gives specific values to an HBP, walk, single, double, triple, and a home run. Batting average and OBP can’t tell the difference between a walk and a double, but slugging percentage values a double twice as much as a single. This is the answer wOBA attempts to answer. It’s also on the scale of OBP.

In 2022, when Ji-Man Choi stepped to the dish without the shift, he had a .415 mark. This was the 11th-highest wOBA with no shift in at least 50 plate appearances. So why is this of note? Well, there are two reasons.

The first is the shift ban. Technically, the shift, in general, is not banned, but the way we know it now will no longer be allowed. Teams must have two infielders on each side of second base with both their feet on the dirt. While this won’t stop a second baseman from moving closer to first base, a shortstop moving a few steps closer to second base, or the outfielders shifting, it should tone down what we have seen, at the very least. Choi was shifted on a whopping 84% of the time last season.

The second reason is when Choi was shifted on, it severely brought down his overall ability. Choi had a .415 wOBA when the shift wasn’t on. But when the shift was put into motion? Choi had a .304 mark. That’s a 111-point difference. For reference, a 111-point difference in wOBA is the difference between National League MVP Paul Goldschmidt (.419) and Ben Gamel (.308) last year.

Of course, nobody is expecting Choi to go from a .322 wOBA in 2022 to rivaling Paul Goldschmidt just because of the toned-down shift. But an increase from .322 to .350-.360 is well within reason. That’s going from a 110 wRC+ to 125-135 wRC+. You can’t deny the stark contrast between how good Choi was without the shift. Choi should be one of the most beneficial players of the new shift rules. With a fully healthy elbow, Choi has the best opportunity as any Pirate to break out next season.

Robert Stephenson – 44.4% Slider Whiff Rate

Calculating whiff is pretty simple. It’s the number of swings and misses divided by the number of total swings taken. Robert Stephenson stands out with a 44.4% whiff rate on his slider, making it a truly deadly weapon. Stephenson made some major adjustments to his pitching repertoire with the Pittsburgh Pirates, and it worked out well for him after the acquisition.

It was only 13 total innings, but Stephenson held batters to a .170 batting average and .264 wOBA with his slider. There were only 13 pitchers in 2022 that faced 100+ batters and had a whiff rate of 44% or higher, and Stephenson was one of them. With a 44.4% whiff rate, you’re talking about a pitch that gets more swings and misses than Gerrit Cole’s slider or Dylan Cease’s slider.

So how can the Pirates take advantage of this? Well, it looks like they already have. Stephenson’s slider usage rate was just 45% during his time with the Colorado Rockies. However, after the Pirates claimed Stephenson off waivers, he used his slider nearly 70% of the time (69.4%, to be exact). He used his fastball a whole lot less as well, going from 53.6% to just 28.2%. There’s a good reason, as while his slider was nasty, his fastball was demolished to a .459 wOBA.

That big change in pitch arsenal will significantly work in Stephenson’s favor next season. Batters can’t hit his slider, and using it about three-quarters of the time seems like a no-brainer move. Sure, his fastball still isn’t great, but he also started to re-incorporate his curveball into the mix, which could even further lessen his four-seamer usage.

Dauri Moreta – .103 Opponent Batting Average On Slider

The Pittsburgh Pirates acquired Dauri Moreta from the Cincinnati Reds for Kevin Newman. Moreta was a rookie in 2022 but struggled. The right-hander pitched 38.1 innings, posting a 5.40 ERA and 5.80 FIP. But there were positives, including his 24.4% strikeout rate, 8.1% walk rate, and 1.17 WHIP. There were plenty of positives to draw from Moreta’s season that the surface numbers don’t tell you, but what I want to focus on here is his slider.

When Moreta threw his slider, he held opponents to just a .103 batting average. Now sure, batting average is far from the best indicator of success, but .103 is out of this world amazing, no matter how you spin it. But it’s not as if he gave up a ton of extra bases in the few times opponents did make contact.

Moreta’s slider also held opponents to a .207 slugging percentage and .200 wOBA, along with a 25% hard-hit rate. If you thought Stephenson’s 44.4% slider whiff rate was great, wait until you see Moreta’s. He had an even greater 48.9% rate. That made it the 28th hardest slider to make contact within 2022.

Like with Stephenson, the Pittsburgh Pirates can take advantage of this by simply having Moreta throw his slider more. Moreta’s sinker ran him into a ton of trouble in 2022. It’s either a pitch he should work on immensely or drop entirely. If he does decide to drop it entirely, his slider should become one of his most-used pitches in 2023. There’s no questioning that it was one of the best of its kind during his rookie campaign.