49ers beat Chargers

SANTA CLARA, Calif. — San Francisco’s No. 1 offense still looks shaky two weeks from the regular season, and the 49ers did just enough for their first preseason victory in a 21-7 win against the San Diego Chargers on Sunday.

There were tens of thousands of empty seats hours after an overnight 6.0-magnitude earthquake struck in the Northern California wine country near Napa. The quake affected some public transportation options to the new $1.2 billion stadium, which sold out last Sunday.

The patchy field is still hardly ideal, with visible lines where new sod was placed Friday after the initial turf failed to hold.

Phil Dawson kicked a 39-yard field goal at the 9:27 mark of the second quarter, ending an eight-quarter scoreless drought for the 49ers as they doubled their preseason total. Dawson added another from 28 yards a week after missing twice.

Backup Blaine Gabbert threw a 6-yard touchdown pass to Vance McDonald late in the first half for the 49ers’ first TD of the preseason. That capped a drive in which Gabbert went 5 for 6.

Philip Rivers completed his first five passes and finished 9 of 10 for 85 yards and a touchdown. San Francisco’s Colin Kaepernick was 6 of 12 for 59 yards.

Bengals 19, Cardinals 13: In Glendale, Ariz., Cincinnati’s Terence Newman returned an interception 54 yards for the only touchdown by either team’s starters, and the Bengals topped the Cardinals.

Mike Nugent added field goals of 48 and 36 yards for Cincinnati (1-2).

Rams

BRADFORD OUT FOR YEAR WITH ACL TEAR: In St. Louis, Rams quarterback Sam Bradford has a torn ACL in his left knee for the second straight year and is out for the season.

Coach Jeff Fisher confirmed the extent of the injury Sunday night, news first reported by ESPN and the St. Louis Post-Dispatch.

In all, five starters were hurt against the Browns.

Cornerback Trumaine Johnson was carted off with a knee injury and three others — guard Rodger Saffold and defensive tackles Kendall Langford and former LSU standout Michael Brockers — left with ankle injuries.

Panthers

NEWTON HAS HAIRLINE RIB FRACTURE: In Charlotte, N.C., quarterback Cam Newton will miss the Carolina Panthers’ final preseason game after an MRI on Sunday revealed a hairline fracture in his ribs.

Panthers coach Ron Rivera said Newton will be evaluated at the end of the week, but expects the two-time Pro Bowl quarterback will be ready for Carolina’s Sept. 7 regular season opener against Tampa Bay.

Broncos

PRATER FACES 4-GAME BAN: In Denver, Matt Prater’s lawyer said the NFL initially threatened a yearlong suspension before agreeing to ban the Denver Broncos kicker four games for violating the league’s substance abuse policy.

Harvey Steinberg said Prater’s suspension was alcohol-related. He said Prater consumed a couple of beers while on vacation in between the end of the team’s offseason workout program in June and the start of training camp in late July.

Prater has been in the league’s substance abuse program since he was charged with DUI on Aug. 12, 2011.