That means Downs will miss a minimum and a maximum of seven games, which eliminates from from participating in the three-game series against the Red Sox at Angel Stadium in Anaheim.
Downs is 1-1 with a 3.08 ERA in 44 games this season, with 25 strikeouts and 13 walks in 38 innings. He also has nine saves this year. Downs, 36, is in the second season of a three-year contract signed with the Halos before the 2011 season.
Since the All-Star break Downs has allowed 12 runs in eight innings, after giving up just two runs in 30 innings in the first half. But Downs hasn't been alone in second-half struggles, as the Angels bullpen has a 5.53 ERA in 42 games since the break.
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