Rockies Pitching Prospect Caps Remarkable Turnaround With August Award

A trip to Double-A has done Stu Flesland III some good.

Stu Flesland pitching for the Washington Huskies. Credit: Washington Athletics | Washington Athletics

Stu Flesland III capped off an excellent August by being named Colorado’s Organizational Pitcher of the Month. Across six starts, the 25-year-old posted a 1.29 ERA and 0.97 WHIP over 35 innings, holding opponents to a .185 batting average. It has been quite the bounce-back after being taken behind the woodshed in Triple-A, and his return to Double-A appears to have allowed him to iron out some of the issues that plagued him earlier in the season.

A Rocky Start

Stu Flesland Posing For Photo In Avista Stadium | The Spokane Review

Flesland has bounced between High-A, Double-A, and Triple-A this season, with his brief stint in Albuquerque easily representing the low point. Across two Triple-A appearances and four innings, he allowed 11 runs before being reassigned to Double-A Hartford. After initially working mostly out of the bullpen, Flesland returned from the injured list on July 3 as a starter and has remained in the rotation ever since.

Flesland has an unconventional pitch mix. His fastball averages around 91 mph, according to FanGraphs, but he actually uses it less frequently than his slider, which sits around 78.5 mph.

His slider will likely be his defining pitch. The left-hander throws from a three-quarters arm slot, giving the offering a sweeping look that can make up for its lack of velocity. When sequenced properly, the pitch can be a slap in the face to hitters expecting something harder, with his sinker and changeup averaging around 91 and 86 mph, respectively.

Stu Flesland III shoved for Hartford tonight. #NoGoatsNoGlory

4.0 IP
1 H
0 ER
0 BB
6 K pic.twitter.com/pQoqpEsd7G

— Blake Street Banter ⚾🌮 (@blakestbanter) July 10, 2026

While Flesland used the slider to retire a right-handed hitter in that clip, lefties have given him even less trouble overall. Opposing right-handed batters own a .708 OPS against him, compared with just .607 for left-handed hitters, according to Statcast.

The split suggests his sweeping slider could be especially troublesome for same-side hitters. Some of that advantage may simply come from the natural difficulty left-handed batters face against left-handed pitching. Without pitch-level tracking data for his Double-A outings, it would be difficult to attribute the platoon split to one offering with certainty.

What this sportswriter is certain about is that Flesland understands the importance of keeping hitters off-kilter. During a 2025 stint with Spokane, he told The Spokesman-Review that he was “mixing it up, throwing changeups and sliders in counts that the hitters wouldn’t expect.” That unpredictability will be especially important for a pitcher whose fastball arrives at roughly the same velocity as some major-league sliders and changeups.

Flesland has proven that Double-A hitters are no match for him, and the next step will likely be another crack at Triple-A. If his slider remains sharp and he continues to keep hitters off balance, his second stint in Albuquerque could look much different than his first.