Travis Hafner

Indians designated hitter Travis Hafner will undergo knee surgery and miss four to six weeks. The team placed him on the disabled list, retroactive to May 24, before Wednesday's game with the Royals.

Hafner, 34, is hitting .242/.380/.439 with six home runs in 39 games. He will have an arthroscopic procedure to repair fraying and irritation in his right meniscus, the Associated Press reported.

The team called up left-hander Scott Barnes from Triple-A Columbus. After starting the season as a starter, Barnes was moved to the bullpen. He's 0-2 with a 3.81 ERA overall in 11 games with 30 strikeouts in 28 1/3 innings. In his eight relief appearances, he has an ERA of 2.19 ERA. After allowing two earned runs in his first relief outing, he's allowed just one since.

The Indians now have seven players on the disabled list -- Hafner, third baseman Jack Hannahan, catcher Carlos Santana, reliever Rafael Perez, outfielder Grady Sizemore and starter Carlos Carrasco.

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