The Green Bay Packers paid a high price in their victory over the San Francisco 49ers this afternoon at Lambeau Field.

Veteran cornerback Al Harris has been lost for the season with a torn ACL, according to a league source.

Harris, who turns 35 next month, was injured in the fourth quarter. He was running in coverage with 49ers wide receiver Michael Crabtree when he went down. Harris was taken by cart to the locker room.

Harris and Charles Woodson have been one of the strengths of the Packers’ defense, and he’s been a model of durability throughout his career. Harris missed four games last season with a spleen issue, but had played in 16 games in five previous seasons for Green Bay.

In Harris’ absence, the Packers will likely have to rely more on Tramon Williams. He wasn’t the only serious injury concern for the team either. Pass rusher Aaron Kampman went down in the third quarter with a left knee injury. His knee buckled, and he made it to the sideline before taking a cart to the locker room.

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