Milwaukee, WI (SportsNetwork.com) - The Washington Nationals placed reliever Aaron Barrett on the 15-day disabled list Friday with a right biceps strain.
The 27-year-old righty left Thursday's game against Milwaukee in the eighth inning. After recording two outs and allowing an RBI single, he pitched two balls to Hernan Perez before exiting the game with a trainer.
Barrett leads Washington pitchers with 30 appearances this season and has a 5.06 ERA in 21 1/3 innings.
To take Barrett's place on the 25-man roster, Washington activated righty David Carpenter, acquired Thursday from the Yankees in a trade that sent infield prospect Tony Renda to New York. Carpenter, 29, had a 4.82 ERA in 18 2/3 innings for the Yankees in 2015.
In 210 career appearances for the Astros, Braves and Yankees, Carpenter owns a 3.73 ERA and 212 strikeouts in 205 1/3 innings, all in relief.