Rivers completed 17-of-23 passes, including a 28-yard touchdown to Malcom Floyd, in the Chargers' (7-7) third straight victory. The Chargers are now tied with Oakland for second place in the AFC West and sit a game back of Denver for the top spot in the division.
Joe Flacco went 23-for-34 through the air for 226 yards and two scores, but was intercepted twice in the third quarter as the Ravens (10-4) had their four-game win streak snapped.
Baltimore was guaranteed a playoff spot prior to the game, though, thanks to losses by the Jets and Titans earlier on Sunday.
Ray Rice carried the ball 10 times for 57 yards while also hauling in nine passes for 55 yards in a losing effort.