Rangers reliever Mike Adams is out "indefinitely" with an aggravated trapezius (shoulder) injury, Jeff Wilson of the Fort Worth Star-Telegram reported Friday. According to Wilson, the same injury popped up earlier in the month. Adams went a season-long eight days between appearances from Sept. 11 to Sept. 19.

September has been a struggle for Adams beyond the injury. In 8 1/3 innings covering nine appearances, the 34-year-old has allowed three home runs, walked five batters and given up a whopping 14 hits, all resulting in a 7.56 ERA.

The struggles have elevated Adams' ERA to 3.27, still good for a 138 ERA+ in hitter-friendly Texas. But Adams has been one of the most dominant relievers in the league since returning from multiple knee surgeries in 2008. From 2008 through 2011, he posted an ERA+ of 153 or higher each season.

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