Quarterback Philip Rivers wasn't kidding about the San Diego Chargers' resolve to run the ball this season.

That was the plan before Ryan Mathews sprained his right knee in a win in Week 2 against Seattle.

And nothing changed in a 22-10 win at Buffalo on Sunday. That's when the Chargers were forced to turn to third-stringer Donald Brown once Danny Woodhead was carted off after hurting his right ankle on San Diego's second play from scrimmage.

"Guys are going to have to step up, and we have to stay balanced," Rivers said. "We can't turn this into, 'Oh, now we're going to be a 50-passes-a-game team.' It just doesn't work."

Though Brown's numbers — 31 carries for 62 yards — weren't eye-popping, the mere threat of Brown running the ball kept the Bills' respected pass-rush on its heels in a game the Chargers (2-1) never trailed.

Rivers was sacked only once in finishing 18 of 25 for 256 yards passing, with a pair of touchdowns to Eddie Royal.

Brown was happy to contribute, and his 31 carries were the most by a Chargers player since LaDainian Tomlinson had that many in 2006.

"I feel good, though tomorrow I'll probably be sore," Brown said. "Whether it's one carry or all the carries, whenever your number's called just make the most of the opportunity."

Brown is no stranger to carrying a big load after the diminutive 5-foot-10 player set numerous school records at Connecticut. He spent the past five seasons in Indianapolis before signing with the Chargers as a free agent in March.

The Bills' feel-good start to the season was derailed in dropping to 2-1.

Buffalo was limited to 208 yards offense and 13 first downs before a final mean-nothing drive ended with EJ Manuel throwing an incompletion into the end zone on fourth down.

The Bills' defense was picked apart by Rivers and a ball-control attack that featured three scoring drives that lasted 6-plus minutes.

"They beat us and they played better than we did today," defensive tackle Kyle Williams said. "But we didn't help ourselves."

Here's a number of other things that stood out in a game between two original American Football League rivals:

WEAPONS APLENTY: A week after Rivers threw three touchdown passes to veteran tight end Antonio Gates, the quarterback found other go-to receivers.

Royal scored on 3- and 5-yard passes, and Malcom Floyd had two 49-yard catches that set up a touchdown and a field goal.

"Philip just opens up everybody," Floyd said. "We've got all kind of weapons on the field. It's pretty much just picking your poison."

TURNING POINT: San Diego took control on consecutive possessions spanning halftime.

Nick Novak capped a seven-play, 61-yard drive with a 37-yard field goal to put the Chargers up 13-3 with 21 seconds left in the second quarter.

Rivers opened the third quarter by marching the Chargers on a 14-play, 80-yard drive, which he capped with a 5-yard pass to Royal. Rivers completed four of six attempts for 56 yards on the drive, and converted all three third-down chances.

"We were tired of getting field goals," Royal said about ending the drive with a TD.

SPUTTERING BILLS: Fred Jackson scored on an 11-yard catch and run top cut the Chargers' lead to 20-10 late in the third quarter.

The Bills, however, managed 22 net yards offense on their next four drives, which ended with two punts, a failed fourth-down attempt and quarterback EJ Manuel giving up a safety when he was penalized for intentional grounding in the end zone.

OUT OF SYNCH: Manuel finished 23 of 39 for 238 yards, but had difficulty getting in synch with his receivers. Rookie Sammy Watkins had two catches for 19 yards despite having eight passes thrown his way.

BANGED-UP BILLS: Starting left guard Chris Williams left in the first half and did not return because of a back injury that has nagged him for much of the past month.

Receiver Marcus Easley hurt his left knee while blocking on a kickoff return midway through the third quarter. Easley was treated on the sideline before being carted off.

Safety Da'Norris Searcy was escorted to the locker room late in the third quarter with what the team called an ankle injury.

Coach Doug Marrone had no updates on the status of his injured players.

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