Key Diamondbacks Reliever Begins Rehab Assignment

The Arizona Diamondbacks should be getting one of their key veteran relief arms back from a lengthy stint on the Injured List very soon.

Right-handed sidewinder Ryan Thompson will begin a minor league rehab assigment in Triple-A on Tuesday night, the Reno Aces announced on X/Twitter.

Arizona Diamondbacks Ryan Thompson Begins Rehab Assignment

Thompson went down with what was designated as a right Scapular (shoulder/back) strain all the way back on July 6.

It's been a somewhat slow return process, though Thompson has been throwing live BP sessions over recent days.

Thompson will head to Reno to build back up to full speed. As the Pacific Coast League is a hellish environment for pitchers, Thompson's overall results in Reno will hardly be taken as much of an indication.

Movement and maintained velocity will be the more important factors to consider.

The veteran righty does not have what would be considered positive stats for this season — a theme that's been pervasive in Arizona's bullpen struggles.

He's thrown to a 4.45 ERA over 32.1 innings, striking out 30 while walking 12 in relief.

He suffered a handful of blowup outings in the early goings of 2025, but had recently settled in admirably. In fact, Thompson had given up just one earned run since May 19 — a span of 17 appearances.

For the month of June, he posted an 0.96 ERA and was beginning to collect ground balls at a high rate once more. In a bullpen full of instability and a bevy of other injuries to key arms, Thompson stepped up as one of the lone reliable members.

Unfortunately, he's been sidelined for nearly two months.

It may be a process for Thompson to return to full form after suffering an injury of that type. Though he did not undergo surgery, that lengthy of an absence after a shoulder injury can put a ceiling on a pitcher's effectiveness in his immediate return.

The Diamondbacks' bullpen has continued to lose arm after arm throughout the course of what has been a brutal 2025 season. In terms of injuries, Arizona has sustained more than its fair share.

That's led to a carousel of late-inning relievers, made up of young arms and journeymen alike. Arizona recently set an MLB record for most players to record a save for one team in a single season.

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But, finally, the D-backs will see the return of one of their injured arms. As of this writing, it's unknown if Thompson will make multiple rehab appearances, or how close he is to rejoining Arizona's major league roster.

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