Pittsburgh Pirates starting pitcher Jeff Karstens will be skipped in the rotation due to a hip flexor injury, according to the Pittsburgh Tribune-Review's Rob Biertempfel.

Karstens in 5-4 in 15 starts this season with a 3.89 ERA and 1.18 WHIP.

Jeff Locke, who was promoted Saturday when rosters expanded around the league, has taken Erik Bedard's spot in the Pirates rotation, but the team has yet to announce who will replace Karstens.

Kevin Correia, who has made 22 starts for the team this season but is now pitching as a reliever, seems like the logical candidate to move into the rotation.

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