The Cardinals recalled O'Brien from Triple-A Memphis on Tuesday, Katie Woo of The Athletic reports.

The Cardinals activated O'Brien (forearm) from the 60-day injured list Sunday and optioned him to Triple-A Memphis.

O'Brien (forearm) could be activated from the 60-day injured list next week after making two more rehab appearances with Triple-A Memphis, John Denton of MLB.com reports.

O'Brien (forearm) will begin a rehab assignment with Triple-A Memphis on Friday, John Denton of MLB.com reports.

O'Brien is scheduled to throw live batting practice Saturday at Double-A Springfield and could start a rehab assignment next week if Saturday's session goes well, John Denton of MLB.com reports.

Cardinals manager Oliver Marmol said that O'Brien (forearm) will throw a live batting practice session at Double-A Springfield on Wednesday, John Denton of MLB.com reports.

O'Brien will throw a live batting practice session Saturday and will begin a rehab assignment at Double-A Springfield on Tuesday if the live BP session goes well, John Denton of MLB.com reports.

O'Brien (forearm) will throw a bullpen in the next day or two, Lynn Worthy of the St. Louis Post-Dispatch reports Tuesday.

O'Brien experienced renewed pain in his right forearm following his 20-pitch live batting practice session with Double-A Springfield on June 15 and underwent further testing and and consultation with Dr. Keith Meister, MLB.com reports.

O'Brien (forearm) will begin a rehab assignment Saturday at Double-A Springfield, John Denton of MLB.com reports.