Some of the Pirates' best relief prospects will be stationed at Triple-A. Their best, Colin Selby, will likely be the go-to 9th-inning man until he gets called to the major leagues, assuming he starts the year at Indy. In 35.2 innings, Selby had a 2.27 ERA, 2.92 FIP, and 1.21 WHIP. Selby struck out nearly 30% of the opponents who stepped into the box against him (28.9%, to be exact). While getting strikeouts was one of his strengths, his biggest strength was his 54.4% ground ball rate and 0.50 HR/9 rate. The only area in which Selby struggled was limiting walks, but even then, his 9.4% walk rate was still serviceable.
Selby was hitting the upper-90s with a slider that generated a chase rate of nearly 50% (48% per FanGraphs). He also throws an above-average 11-5 curveball. Selby has so-so command but has seemingly overcome that to post fantastic results. With his inclusion on the 40-man roster, Selby might end up getting consistent high-leverage innings next season for the Bucs.
Tahnaj Thomas finally broke out as a relief prospect with a quality Double-A campaign. Now, he'll get reps at Triple-A. He did get off to a slow start for Altoona, but by June, he was fully acclimated to his new role. In his final 36.1 innings of the year, Thomas had a sub-2.00 ERA (1.98) and a strong 2.70 FIP. He also had a WHIP of just 1.05. Thomas, who previously struggled with walks, dished out a free pass to just 6.9% of opponents while striking them out at a 28.5% rate. He also had an HR/9 of 0.50.
Thomas consistently works in the upper-90s and can even hit triple digits. His slider is well above average, though his change-up has always been a work in progress at best. It's always the deciding factor as to whether or not he'd end up as a starting pitcher or reliever. Thomas previously struggled with walks but has seemingly overcome his struggles with control.
One of the organization's more interesting relief prospects, J.C. Flowers, will also be part of Triple-A's bullpen. Flowers was an outfielder throughout his college career and switched to the mound in his final season. He brings that athleticism to the mound, even with little experience as a pitcher. Like Thomas, Flowers also got off to a slow start but was fully settled in by June. Through his last 38 frames of the 2022 campaign, Flowers had a 2.61 ERA, 1.03 WHIP, and 3.31 FIP. The right-hander struck out 27.3% of opponents with a 0.47 HR/9. His walk rate clocked in at 9.1%.
Flowers typically sits in the low-mid 90s, but his slider is a devastating weapon. It's a truly elite pitch that he can use to get swings and misses. His changeup also projects to be average. Flowers was primarily used in long relief at Altoona and was previously used as a starting pitcher in the low levels of the minor leagues. It will be interesting to see how he's utilized from here on out. He's different than your typical pitching prospect, given his lack of experience on the mound and the athleticism of an outfielder.
Another long-relief/swing-man type prospect who will be in Indy's pitching staff is Cody Bolton. Bolton has had a very up-and-down professional career. After a strong start in 2017-2019, Bolton then missed two seasons. The first was in '20 because of the canceled minor league season, then in 2021 because of injuries. But he had a fine rebound season, working to a 3.09 ERA, 3.81 FIP, and 1.28 WHIP. Bolton had a decent 25.4% K% along with an outstanding 0.48 HR/9. However, there were some red flags. Despite his outstanding HR/9, he had an HR/FB ratio of just 5.1%. He also handed out free passes to 12.4% of opponents faced.
Bolton sits about 92-94 MPH with his fastball, but he does throw an above-average slider. He spins it well, averaging about 2700 RPM. Bolton also throws a changeup, a third pitch that projects as average or better. But Bolton's command is sub-par at best. It would be interesting to see if a mechanical change could benefit Bolton. Bolton has a violent, whippy-like arm motion, something that FanGraphs highlights, and could benefit from shortening his arm up like Max Kranick.
Some of their top left-handed relief prospects will also be part of the same Triple-A bullpen. The best of this duo is Tyler Samaniego. A 15th-round pick, Samaniego had a 2.45 ERA, 3.46 FIP, and 0.90 WHIP across 47.2 frames. Samaniego struck out just over a quarter of the batters he faced with a 25.5% strikeout rate, however, limiting home runs and inducing ground balls is the southpaw's specialty. He had a 56.6% ground ball rate, and his 0.38 HR/9 was one of the best among Pirate minor leaguers. The downside is he ran into walks at a 10.9% rate.
Samaniego works in the low-mid-90s with a slider and a change-up. There were some red flags with Samaneigo's season. Despite cutting his walk rate down from 18.9% to just 7.8%, he also saw his strikeout rate plummet from 35.3% to just 19.8%. He still had a respectable strikeout rate overall, but the large drop is a bit concerning. But on the plus side, he at least significantly cut down on the free passes.
The other noteworthy left-handed relief prospect is Nick Dombkowski. Dombkowski was an undrafted free agent but had outstanding numbers last year. He managed a 3.07 ERA, 3.29 FIP, and 1.10 WHIP through 67.1 innings. Dombkowski had a 0.94 HR/9 rate; however, he had a strong 30.7% strikeout rate and 6.8% walk rate. The southpaw's 4.58 K:BB ratio was the best in the Pirate system among pitchers with 60 or more frames under their belt last season.
Dombkowski is not a flamethrower. He only sits in the upper-80s and low-90s and tops out at 93-94 MPH. However, his slider and change-up are above average, the latter of which is considered a 60-grade pitch by FanGraphs. But his stuff plays up to a certain degree because of his above-average command.