Keller’s changeup sits at a comfortable 91 mph, but he did not utilize it much in his first season in the league (5%). This is not surprising as it is considered his worst pitch based on his prospect report. He threw 26 of his 28 changeups against lefties and allowed four hits in five at-bats.
Everyone is excited about Keller’s secondary offerings, and the curve flashed the most brilliance in his debut season. Sitting at a nice 81.1 mph, Keller just threw it 14.3% of the time but the results were mouthwatering: a 37.1 K% with hitters producing a meagre .207 xWOBA aginst it.
Keller’s fastball is considered his best pitch (60/60 on the 20-80 scouting scale) which is why he used it 60% of the time this season. However, he struggled with it, allowing 41 hits in 89 at-bats with 16 of those going for extra bases. He did throw it 70% of the time for a strike and had very good velocity (95 mph average), so there is definitely some upside despite the bad results he got.
Keller’s slider was his put-away pitch this year, striking out 18 batters in 47 plate appearances thanks to the elite 48% whiff rate and 27% swinging strike rate he generated with it. He also held batters to only nine hits in 45 at-bats while allowing only two walks.