Pittsburgh Pirates: Examining Newly Acquired Zach Thompson

The Pittsburgh Pirates acquired Zach Thompson as part of the Jacob Stallings trade. But what is the right-handed pitcher bringing to the table?

The Pittsburgh Pirates got back a pitcher with MLB experience in the Jacob Stallings trade. That was right-hander Zach Thompson. Thompson seemed to come out of nowhere as 2021 was his age-27 campaign. But he ended up getting regular starts in a rotation that housed some pretty notable names including Sandy Alcantara, Trevor Rogers, and Pablo Lopez. Thompson had a solid rookie season, working as a swingman (26 total games, 14 starts). So what does the right-hander bring to the Pirates?

Through 75 innings, Thompson worked to the tune of a 3.24 ERA, 3.69 FIP, and 1.21 WHIP. Overall, pretty solid numbers. This also came with a phenomenal 16.5% line drive rate and solid 43.4% ground ball rate. Thompson only allowed 6 home runs for a 0.72 HR/9. Plus he was well above average in limiting hard contact. He was in the top 76th percentile of exit velocity at 87.6 MPH, and the top 82nd percentile of hard-hit rate at 34.4%.

Thompson’s fastball was in the top 92nd percentile of spin rate. But he’s not a hard thrower. His four-seamer only averages out at 92.2 MPH. His primary pitch is a cutter but also tosses a curveball, changeup, and sinker with regularity.

Among Thompson’s offerings, his cutter was the most effective. It had a run value of -11 and RV/100 (run value per 100 pitches) of -2.7. Overall, it was the 7th most valuable cutter in the sport, tied with Kenley Jansen’s and Luis Garcia’s cutters. On a rate basis, it was the 14th best cutter. Overall, he’s average or better in all of Baseball Savant’s stats except for strikeout, walk rates, and curveball spin.

So what’s the catch? Well, the numbers under the hood aren’t very pretty. Thompson had a poor 4.65 xFIP, which was about 10% worse than the league average. He also had a 4.58 SIERA compared to the league average mark of 4.18. DRA was the kindest to him. While it pegged him at 4.64, it was roughly league average with a 100 DRA-. Overall, he had an 8.9% walk rate and a 21% strikeout rate. As stated earlier, both were below-average marks.

Thompson’s underlying numbers are worrisome. Sure, some pitchers can outperform their expected numbers by fair margins on a consistent yearly basis, but they are few and far between. Hopefully, Thompson is one of those pitchers. If Thompson can be a solid #4 starter, he’ll be more than serviceable for the Pirates. On the upside, none of his expected stats on Baseball Savant are below average and his most advanced ERA estimator, DRA, is about league average.