The Yankees activated reliever Adam Warren off the disabled list prior to Game 2 of Monday's doubleheader against the Detroit Tigers and optioned reliever Tommy Kahnle to Triple-A Scranton/Wilkes-Barre.
Warren has not pitched since April 20 and has a 3.24 ERA in eight relief outings this season, striking out 11 batters in 8 1/3 innings.
The 30-year-old returns from the disabled list after straining his back in April. Last season, he recorded a 2.35 ERA with one save, three blown saves and 11 holds in 46 relief outings.
The Yankees opted to keep relievers Chasen Shreve and Jonathan Holder on the 25-man roster over Kahnle, who has given up 11 runs (seven earned), six hits and 10 walks in nine innings across eight relief appearances this season.
Last year, Kahnle recorded a 2.70 ERA in 32 relief appearances with the Yankees after a mid-season trade.