An Illinois high school product, Schlaffer received an over-slot $250,000 bonus as a ninth-rounder in 2019. His development was delayed by losing all of 2020 to the pandemic and all of 2023 to recovery from Tommy John surgery, but he has emerged as one of the best starter prospects in a pitching-thin Cubs system since his return. Promoted to Double-A this July, he permitted just eight runs in his first five starts there.
Schlaffer works with a fringy fastball that sits at 91-94 mph, touches 97 and features some armside run. He uses it to set up a pair of solid secondary pitches, the better of which is a low-80s curveball with power and depth. While his mid-80s changeup doesn't induce many chases, it fades so much that right-handers have a hard time making in-zone contact against it.
Schlaffer isn't very physical at 6-foot-1 and 180 pounds, but he gets down the mound well to create some extension. He generates his stuff more with arm speed than effort, though his control and command are just fair. He could reach Chicago as a back-of-the-rotation starter or middle reliever in 2026.
