Philip Rivers threw his third touchdown pass and San Diego’s defense stuffed Matt Cassel on fourth-and-goal from the 1-yard line as the Chargers took a 27-3 lead over the nemesis New England Patriots after three quarters Sunday night.

This was a rematch of the AFC championship game, which the Patriots won 21-12, and the fifth time in four seasons the teams have met. The Patriots have won three straight against San Diego, including eliminating the Chargers from the playoffs the last two seasons.

With Tom Brady and Shawne Merriman out for the season with knee injuries, this prime-time matchup lost some of its luster.

Rivers did his best to pump it up, though, by throwing three TD passes for the fourth time this season. Rivers drew raves for his toughness by playing the AFC title game with a shredded ligament in his right knee, but couldn’t get the Chargers into the end zone that day.

Tight end Antonio Gates slipped into the end zone and caught Rivers’ 1-yard pass with 7:07 left in the third quarter Sunday night to cap a 98-yard, four-play drive. Rivers had a 59-yard completion to Vincent Jackson on the second play. The Chargers got the ball at the 1 after Jackson was dragged down by Ellis Hobbs, who was flagged for pass interference.

San Diego’s defense came up huge after the Cassel led the Patriots to a first-and-goal at the 1 on the opening drive of the second half. After Cassel threw two incompletions and running back Sammy Morris was stuffed, Cassel dropped back on fourth down. With all his receivers covered, he attempted to run up the middle but was buried at the 2.

Rivers threw a touchdown pass of 49 yards to Malcom Floyd and another of 4 yards to Jackson in the first half.

Floyd’s first catch in almost a year was a big one. With wide receiver Chris Chambers inactive due to a sprained ankle, Floyd benefited from extra playing time. He ran a post pattern and outjumped cornerback Deltha O’Neal for the ball before tumbling into the end zone with 3:58 to go in the first quarter.

It was Floyd’s first catch since Oct. 14, 2007, and his first touchdown since the 2006 season. He was inactive the final 10 regular-season games and all three playoff games.

Rivers threw a 4-yard scoring pass to Jackson just before halftime. Jackson was wide open after cornerback Ellis Hobbs ran into safety James Sanders.

The Patriots (3-1) remained in California following their win at San Francisco a week earlier.

LaDainian Tomlinson became the 17th player to rush for more than 11,000 career yards.

San Diego’s Nate Kaeding kicked field goals of 25 and 35 yards. New England’s Stephen Gostkowski was wide left on a 48-yard attempt but later hit a 47-yarder.