AP

The only losses that matter in the preseason relate to injuries. The Chargers may have suffered a significant one today in San Francisco.

Nose tackle Kwame Geathers suffered a left leg injury while taking on a pair of 49ers’ offensive linemen in the first quarter of Sunday’s preseason game. Replays show the left knee appearing to give out while Geathers was taking on the two blockers.

Geathers left the game via cart. He had moved up to the starting lineup after Sean Lissemore suffered an ankle injury in the second week of the preseason.