Diamondbacks to Place Struggling Pitcher on IL in New Roster Move

The Diamondbacks are expected to make a roster move.

Jul 3, 2026; Phoenix, Arizona, USA; Arizona Diamondbacks pitcher Ryan Thompson against the Milwaukee Brewers at Chase Field. Mandatory Credit: Mark J. Rebilas-Imagn Images | IMAGN IMAGES via Reuters Connect

The Arizona Diamondbacks will have to do without one of their veteran leverage relievers for the time being.

As reported by Arizona Sports 98.7's John Gambadoro, the Diamondbacks will place right-handed sidewinding reliever Ryan Thompson on the Injured List. It is not yet clear what the injury designation will be.

Hearing that corresponding move will be reliever Ryan Thompson to the IL. https://t.co/T7Gh2mHh2W

— John Gambadoro (@Gambo987) August 5, 2026

Subsequently, Arizona is expected to call up left-hander Philip Abner from Triple-A Reno to fill Thompson's roster spot.

Diamondbacks to place Ryan Thompson on IL

Jul 26, 2026; Washington, District of Columbia, USA; Arizona Diamondbacks pitcher Ryan Thompson (81) pitches against the Washington Nationals during the sixth inning at Nationals Park. Mandatory Credit: Geoff Burke-Imagn Images | IMAGN IMAGES via Reuters Connect

It's been a struggle for Thompson of late.

The right-hander has been one of Arizona's most valuable, reliable late-inning arms since he was claimed off waivers in the 2023 season, but he has not looked like his sharp self since June concluded.

In July, Thompson pitched to a 9.00 ERA, giving up 12 runs (10 earned) in 10 innings. He gave up 21 base hits in 11 appearances.

Thompson threw a clean 1.1 innings on August 2 agains the Cleveland Guardians, but struggled again on Tuesday night against the Padres, allowing three hits, a walk and a run while recording only one out.

As such, his season ERA has inflated all the way up to 4.43, after sitting as low as 2.22 on June 16.

Thompson's strength has always been in his unconventional sidewinding delivery and high movement on his sinker and slider. He's never been a high-velocity arm. But it is worth noting his sinker — which is generally his primary pitch — has averaged just 89.3 MPH.

That's down almost a full tick from 2025, and nearly two ticks from 2024. And his command has been rough in recent days, as well. Teams appear to be checking off his high-movement pitches when not in the zone at a higher rate.

Thompson's ground ball rate is 50.7% this season. That's still well above average, but it's down quite a bit from the 60-plus-percent clip he sat at during his dominant 2023 and 2024 runs.

Diamondbacks to call up Philip Abner

Jun 5, 2026; Phoenix, Arizona, USA; Arizona Diamondbacks pitcher Philip Abner (50) throws during the sixth inning at Chase Field. Mandatory Credit: Arianna Grainey-Imagn Images | IMAGN IMAGES via Reuters Connect

This will be Abner's fourth major league stint of the year. He has yet to pitch more than two games during any of his other call-ups.

Abner has a 6.75 ERA in the majors this year, but pitched two straight outings (three innings) in his most recent stint without being charged with an earned run. His 5.01 ERA for the Triple-A Reno Aces looks poor, but is actually well above the PCL average ERA of 5.49.

Abner is not necessarily a leverage arm, but he can provide some length should the D-backs bullpen be heavily taxed. With rookies Kohl Drake and Mitch Bratt set to pitch this series against the Padres, Arizona might need some innings coverage out of Abner.