Warren was recalled from Triple-A Sacramento on Tuesday, Amy Gutierrez of the Giants' official site.
Warren's last stint in the bigs was in 2023 for the Angels before undergoing Tommy John surgery. After signing with the Giants in February, he has recovered and spent the 2024 campaign with Triple-A Sacramento, where he has a 4.95 ERA overall. However, the 28-year-old has not allowed an earned run in his last eight outings and boasts a 1.54 ERA since July 14. In a corresponding move, Jordan Hicks was placed on the 15-day injured list with right shoulder inflammation.