Pittsburgh Pirates: Three Pitchers to Watch in 2024 Based on Stuff+

Stuff+ is a new statistic that measures how good a pitcher's pitch metrics were, so who are some potential Pirates players to watch based on that?
Sep 5, 2023; Pittsburgh, Pennsylvania, USA; Pittsburgh Pirates relief pitcher Hunter Stratton (63)
Sep 5, 2023; Pittsburgh, Pennsylvania, USA; Pittsburgh Pirates relief pitcher Hunter Stratton (63) / Charles LeClaire-USA TODAY Sports
2 of 4

Colin Selby

Colin Selby entered the season as one of the Pirates’ best relief prospects. Selby’s sinker was his primary pitch and was above average in the eyes of stuff+, coming in at 106. The right-hander has velocity on his side as he threw his sinkerball at 96.6 MPH on average, making it the 35th hardest-thrown sinker last year. His curveball, which he threw 17.2% of the time last year and came in around 82-83 MPH, registered at 109 in stuff+. Selby’s curveball had really good movement, with 55.3 inches of drop and 12.1 inches of break. That’s extremely comparable to Aaron Nola’s curve.

Of the pitches Selby threw with some regularity, his slider graded out the best in stuff+, coming in at 127. The reliever threw his slider at 88.4 MPH, the 54th hardest thrown of its kind last year. Selby’s slider had below-average vertical movement at 31.1 inches of drop, but with 6.1 inches of horizontal break, his slider broke just over two inches more than the average slider. Overall, Selby had 114 stuff+.

Selby’s stuff looked good, but he did not perform well. In 24 innings, he allowed 24 earned runs. While he struck out 26.3% of the opponents he faced, he also walked them at a 13.2% rate. Home runs gave him some trouble as well, as he had a 1.50 HR/9. Selby struggled, but there were some promising underlying numbers.

Selby had a 48.5% ground ball rate along with an above-average 88.1 MPH exit velocity. His .385 batting average on balls in play indicates he could probably regress toward the mean. Throughout the minor leagues, he held opponents to a .284 BABIP. Selby also had a 21.1% HR/FB ratio despite having a sub-30% fly ball rate. Selby had a 3.94 xFIP, 4.25 SIERA, and a 94 DRA- (203 ERA-), which point to average to slightly better than average production.