For a team that really only has one pass-rusher, losing that pass rusher for a long period of time could be disastrous for the San Diego Chargers.
Now, we've seen these "Chargers fear this injury" reports before and they don't always turn out accurate. Remember when the team feared Malcom Floyd had tore his ACL and then he didn't? There's reason to believe it could be a strained quad, instead of a torn one.
My understanding about torn quads is basically that Freeney would be out for 2+ months, if that were to be the injury. There'd be a decent chance of Melvin Ingram returning to the field before him. That means that San Diego's pass rushers, going forward, would be Larry English, Jarret Johnson and Tourek Williams. Thomas Keiser, whom everyone liked in the preseason, is on the team's practice squad and would probably get the call.