NFL Week 1 injuries: Chargers' Keenan Allen carted off, RG3 hurt

With their offense rolling against the Kansas City Chiefs, the San Diego Chargers suffered what could be a significant loss.

Wide receiver Keenan Allen was carted off in the second quarter with a non-contact knee injury. The Chargers announced Allen would not return. According to multiple reports, the team fears he has suffered a torn anterior cruciate ligament.

Allen had six catches for 63 yards before leaving the game.

The 24-year-old was looking to re-establish himself this season after missing eight games last season with a lacerated kidney.

Here are the other notable injuries from Week 1 in the NFL:

- Cleveland Browns quarterback Robert Griffin III said he sprained his shoulder against the Philadelphia Eagles but did not expect to miss next week's game.

- Houston Texans linebacker Brian Cushing injured his knee in the first quarter against the Chicago Bears and did not return. NFL Network's Ian Rapoport reported the injury was a torn medial collateral ligament and that Cushing will be out for six weeks.

- New Orleans Saints cornerback Delvin Breaux took a cart to the locker room with a left leg injury in the third quarter against the Oakland Raiders. According to multiple reports, the injury was later determined to be a broken fibula.

- Miami Dolphins defensive end Mario Williams was evaluated for a concussion against the Seattle Seahawks.

- Indianapolis Colts safety T.J. Green suffered a knee sprain against the Detroit Lions and did not return.

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