Padres Announce Casey Mize and Robbie Ray Debut Dates, Nick Pivetta Injury Update

The San Diego Padres made two big pitching additions at the deadline, and are hoping to get two more in the coming weeks.

While right-handed pitcher Casey Mize and left-hander Robbie Ray were added ahead of Monday's trade deadline, on Tuesday, injured right-handers Joe Musgrove and Nick Pivetta began their rehab assignments at Single-A Lake Elsinore.

Musgrove's went better than Pivetta's.

Musgrove completed 2.2 innings, striking out three while allowing one run. Pivetta lasted just 14 pitches before abruptly walking off the mound and right back into the dugout in a concerning scene.

An update from Lake Elsinore.

Nick Pivetta walked off the mound after throwing a pitch and went straight to the dugout. pic.twitter.com/qdpo3eGHZ9
— Sammy Levitt (@SammyLev) August 4, 2026

It appeared that Pivetta suffered what could have been a major setback in his recovery from a flexor tendon injury. However, manager Craig Stammen had a promising update ahead of Tuesday's game against the Arizona Diamondbacks.

Stammen told reporters that Pivetta felt tightness in his elbow but was able to go into the bullpen and throw 20-30 pitches in his bullpen, using all of his pitches.

He said the bullpen session went fine, and the team would know more on Wednesday based on how he feels.

"He felt a little bit of tightness in his elbow, but then he was also able to catch his breath and then go throw 30 pitches underneath the stadium in the batting cage," Stammen said. "So take that for what it's worth, we'll find out how Nick feels tomorrow."

Nick Pivetta felt tightness in his elbow during his rehab start when he came off the mound but then threw 30 pitch bullpen session and felt perfectly fine. The Padres will know more tomorrow how he feels.
— Bob Nightengale (@BNightengale) August 4, 2026

According to Kevin Acee of the San Diego Union-Tribune, there is "some optimism" that he'll be able to continue his rehab.

Felt discomfort on mound. Then he felt OK. It happens sometimes when working back from arm injury.
He let loose in bullpen and evidently did not feel the same thing he did while in game. So there is some optimism he will be able to resume rehab. https://t.co/LJ1VtKRm4p
— Kevin Acee (@sdutKevinAcee) August 4, 2026

Casey Mize, Robbie Ray Debuts Set

As for the new additions, Stammen revealed that Mize, who was officially activated on Tuesday, will make his debut on Wednesday against the Diamondbacks.

Ray is scheduled to pitch on Friday against the Houston Astros. That means Walker Buehler will remain on line to pitch Thursday's series finale against the Diamondbacks.

Mize, 29, has a 2.70 ERA across 16 starts this season with 85 strikeouts to 19 walks over 86.2 innings.

Ray, 34, has a 3.08 ERA across 122.1 innings this season with 107 strikeouts to 57 walks.

Padres Activate Casey Mize, Gage Workman in Major Roster Move

The Padres announced a roster move ahead of Tuesday's game to add two of their deadline additions to the roster.

Mize and infielder Gage Workman were added to the 26-man roster while left-handed pitcher JP Sears and catcher Rodolfo Durán were optioned to Triple-A El Paso.

We have added RHP Casey Mize and INF Gage Workman to the 26-man roster and optioned LHP JP Sears and C Rodolfo Durán to Triple-A El Paso.
— San Diego Padres (@Padres) August 4, 2026

The Padres will need to make another move to add Ray to the roster.

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