Top pitching prospects having growing pains at Double-A, but signs point toward progress

When Reds top prospect Rhett Lowder joined Chase Petty and Julian Aguiar at Double-A Chattanooga in mid-May, the Lookouts could conceivably have marketed the trio as the “rotation of the future.” Since then, Lowder and Petty have scuffled while Aguiar has soared. Despite these divergent paths, it’s no time for Reds fans to worry yet.

Lowder, coming off an MiLB Player of the Week accolade, had a rude awakening after his promotion to Double-A. Over his first three starts, the former first-round MLB Draft pick surrendered 15 runs over 11 ⅓ innings. He allowed a .487 average on balls in play, and his strikeout numbers went down, mustering only 12 Ks over those three starts.

Since then, Lowder has experienced some success in fits and starts. He turned in an 11-strikeout performance on June 4, and he proved he could weather a tough start when he allowed two home runs in his first three innings, then settled down to limit the Blue Wahoos to one hit in his final two frames on June 21.

Reds top prospect Rhett Lowder’s tough adjustment at Double-A may be smoothing out as the first half comes to a close

The most telling aspect of Lowder’s performance at Double-A so far has been the disparity between his ERA and FIP. In 10 starts with Chattanooga, Lowder’s ERA is an eye-popping 6.40, but his FIP is a far more palatable 4.00. Traditionally, gaps of this magnitude are attributed to bad luck, and FIP is understood to be a better predictor of pitching quality. Considering this is Lowder’s first full professional season, his struggles seem like growing pains that may not hold him back from his potential to rise through the ranks for long.

Petty, similarly, has a sizable disparity between his ERA and FIP, but that gap is quickly closing. Over the 2024 season, the Reds’ No. 5 prospect per MLB.com has a 5.16 ERA and a 4.36 FIP. Since the beginning of May, though, Petty has reversed the trend, posting a 3.75 ERA and 3.99 FIP. His luck seems to be stabilizing, but the real concern in Petty’s performance is his control.

Petty has only produced one start without allowing a walk, and he handed out seven(!) free passes in his most recent appearance. Thankfully, he seems to have learned how to pitch around his mistakes, as he did not allow a run in his seven-walk appearance and regularly goes 5+ innings into games, despite what must be an elevated pitch count.

To get a glimpse of their future, these two struggling prospects may not need to look too far. They shared a rotation with Aguiar, who is ranked as the No. 16 prospect and who took a similar path to Chattanooga last year. Like Lowder, Aguiar breezed through High-A and landed with the Lookouts. Like Petty, he struggled with control at the higher level, walking 10 batters across his first four starts. Like both Lowder and Petty, he had a substantial gap between his ERA and FIP.

Aguiar turned things around in 2024. He opened the season with Chattanooga and demonstrated better skills. He reduced his home run and walk rates. He dropped his ERA by nearly a run (notably, his FIP rose by .29). The Reds rewarded him with a promotion to Triple-A Louisville in June.

Reds fans are understandably eager to see Lowder, Petty, and Aguiar at the big-league level sooner rather than later, but if their first-half struggles at Chattanooga indicate anything, the duo needs more time to join their former compatriot.