PHOENIX (AP) — Arizona Cardinals quarterback Kevin Kolb has rib cartilage damage and will be sidelined, in the team’s words, “an unspecified period of time.”

Kolb, who took over when starter John Skelton went down in the opener and directed the game-winning drive, had the team at 4-2 despite weak play by his offensive line that had him sacked 22 times in the last three games.

The job will revert to Skelton, who beat out Kolb for the starting job in the preseason and just now is returning to health from a sprained left ankle.

Kolb was hurt trying to make it to the line of scrimmage on a busted play late in the Cardinals’ 19-16 overtime loss to Buffalo on Sunday.

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