American Football: Recap: Chargers vs 49ers

Philip Rivers looked like an overmatched rookie in the first half. But once he got the chance to play against San Francisco's backup defenders, he showed signs of why the San Diego Chargers believe he's their quarterback of the future.

Rivers completed his first 13 passes of the second half and the Chargers finished the preseason with a 31-15 victory over the 49ers on Thursday night.

San Francisco's defense couldn't stop San Diego on the ground or in the air and the 49ers finished the preseason winless for the first time since 1974.

While Rivers was sharp late, his first-half performance - coupled with Drew Brees' efficient night - might have ended San Diego's quarterback controversy for now.

Rivers, the fourth pick in this year's draft, missed the first two exhibition games in a contract holdout. Despite Rivers' 5-for-14, two-interception performance in his debut against Seattle, coach Marty Schottenheimer said the quarterback battle remained an open competition.

Brees, whose poor play last year contributed to San Diego's decision to acquire Rivers, made his case for keeping the job. He went 5-for-5 for 71 yards, including a 35-yard TD pass to Eric Parker, and led San Diego to 14 points on three drives.

Rivers had just three pass plays in the first - a sack when he held onto the ball too long, an intentional grounding penalty and an interception.

But he settled down in the second half, completing eight passes for 43 yards on the opening drive of the third quarter. He exploited San Francisco's defense with short throws on a 16-play drive, capped by rookie Michael Turner's 2-yard run.

A fumble by punt returner Arnaz Battle set up Rivers' first touchdown pass as a pro - a 4-yarder to Kevin Dyson that made it 31-15 early in the fourth quarter. Rivers finished 13-for-16 for 85 yards.

Both Brees and Rivers were helped by a strong running performance by Turner and Jesse Chatman. With star running back LaDainian Tomlinson sitting out once again to stay fresh for the regular season, Turner ran for 116 yards and Chatman had 65. Both also scored touchdowns.

The 49ers know Tim Rattay is their starting quarterback, and are happy to see him on the field performing well. Rattay missed the first two preseason games with a sore arm and was limited last week against Minnesota.

Rattay underthrew Cedrick Wilson on a deep ball on San Francisco's opening drive, but finished his night with a 41-yard touchdown pass to Brandon Lloyd. Rattay went 7-for-8 for 101 yards.

"I'm glad they let me play a couple of series for me personally to get going," Rattay said. "I think the offense is doing a good job and we're getting different guys involved."

San Francisco's sloppiness was evident on one series in the second quarter. Ken Dorsey had three touchdown passes - to rookie Rashaun Woods, Battle and Aaron Walker - called back by penalties before the 49ers settled for a 19-yard field goal by Todd Peterson.

Woods, who missed the first two preseason games with a hamstring injury, made his first two catches as a pro - an 11-yarder and a 15-yarder.

"That is why we have Rashaun here," coach Dennis Erickson said. "We wanted to get him in a position to see if he can make some plays. He's been hurt and it was good to see him do that."

The 49ers struggled on the ground with starter Kevan Barlow resting, gaining only 19 yards on 16 carries in the first half.

Both teams played their star linebackers for the first time this summer. San Diego's Donnie Edwards, who severely cut his left calf in an accident at home just before training camp, had three tackles in the first half.

San Francisco's Julian Peterson, who held out for 28 days, also played just over a quarter.

"I'm kind of disappointed that they scored on us, but other than that it went pretty well," Peterson said. stinger in his neck.