Kyle Finnegan's Revival
The most recent success story of the Detroit Tigers player development.
July 31, 2025 — The Detroit Tigers acquired right-handed relief pitcher Kyle Finnegan from the Washington Nationals for two pitching prospects, Josh Randall (Detroit’s No. 15 prospect) and R.J. Sales.
Finnegan had spent his entire career with the Nationals (debuted in 2020) and signed a 1 year, $6 million deal to return to Washington for the 2025 season. He was born in Detroit, so it’s a bit of a homecoming to get traded to the Tigers. Finnegan has been a solid back end of the bullpen option his entire career, something Detroit was lacking leading up to the trade deadline. This article is intended to breakdown the improvements we’ve seen since coming over to Detroit and what’s behind the recent success.
Washington Tenure
From 2021-2024, Kyle Finnegan was a reliably, consistent option for the Nationals to turn to at the end of games. 60-70 IP with a mid-3.50 ERA, a slightly above average K%, an average BB%, and back-to-back seasons ranked top 10 in the NL in saves. He struggled preventing hard contact the last two seasons contributing to a higher xERA than actual ERA. (3.76 ERA vs 4.70 xERA in 2023, 3.67 ERA vs 4.34 xERA in 2024). In fact, all expected numbers have gone up since 2022, indicating negative regression and potential future struggles.
The Detroit Tigers clearly saw something they liked in his profile to take a chance on him at the deadline.
Detroit Tenure
Kyle Finnegan has only pitched 11.2 innings with Detroit since the start of August but has made his impact felt in the bullpen. His surface level stats are great: 11.2 IP, 0 ER, 3 H, 2 BB, 15 SO. The K-BB% is phenomenal, improving from 11.0% with the Nationals in the first half of the season to 32.5% with Detroit. Yes, the sample size is limited but the results speak for themself. His season ERA has dropped from 4.24 to 3.38 since joining the Tigers bullpen. How is he getting these improved results? I noticed three key changes to his pitch arsenal.
Arm Angle
Finnegan throws 3 pitches: a four seamer, split finger, and slider and the arm angle on all pitch types has changed since joining the Tigers. Since April to August, here are the average arm angle changes on each of his pitches:
Four seamer: 50° to 53.2°
Splitter: 45.7° to 49°
Slider: 48.3° to 53.4°
I’ll get into why this matters with the following changes.
Vertical Release Point
The point at which Finnegan releases the ball from his hand to the plate has also changed, even looking at a month to month comparison (July to August below).
Four seamer: 5.76 ft to 5.67 ft
Splitter: 5.66 to 5.57
Slider: unchanged
Dropping the vertical release point on his four seamer and splitter, combined with an increased arm angle gives those pitches new characteristics from the batter’s perspective. Although the actual pitch speed hasn’t changed, the path to the plate and perception has altered enough to give hitters troubles.
Pitch Usage
The pitch usage can go along way in changing a pitcher’s outcomes. It sounds simple but sometimes just throwing your most effective pitch, more often, is a recipe for success. Here’s how Finnegan’s pitch usage has changed from July to August:
Four seamer: 64.8% to 46.4%
Splitter: 25.6% to 48.3%
Slider: 9.6% to 5.3%
The slider has minimal changes, so we can ignore that during our analysis. The changes to the four seam and splitter usage are significant though. The Tigers have instructed him to throw the two essentially the same amount of time now. The splitter had the best results prior to coming to Detroit, so with the aforementioned changes (arm angle and vertical release point), it appears the splitter has become an even nastier pitch for him.
Results
Let’s compare the results from July to August on each pitch type, after breaking down the 3 changes the Tigers have made.
Four seamer (July): .348 BA, .522 SLG, .399 wOBA, 11.4 whiff %
Four seamer (Aug): .133 BA, .200 SLG, .207 wOBA, 8.1 whiff %
Splitter (July): .167 BA, .167 SLG, .225 wOBA, 52.6 whiff %
Splitter (Aug): .050 BA, .050 SLG, .044 wOBA, 52.5 whiff %
Slider (July): .250 BA, .250 SLG, .221 wOBA, 14.3 whiff %
Slider (Aug): .000 BA, .000 SLG, .000 wOBA, 33.3 whiff % (only 8 pitches thrown)
Kyle Finnegan came into Detroit as an experienced backend of the bullpen arm with consistently average results. Through changes to his arm angle, vertical release point, and pitch usage, he’s become unhittable. The Tigers pitching development has gotten a lot of praise over the last few seasons and Finnegan is another example of why. A great add by Detroit and hopefully we continue to see dominant outings from Finnegan throughout the remainder of the season.
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