SAN DIEGO — Brock Osweiler and the Denver Broncos got a remarkably easy victory Sunday against the San Diego Chargers.

It probably helped that the thousands of orange-clad fans made it feel more like a home game. And it certainly helped that they were playing the hapless Chargers.

Osweiler threw a 3-yard touchdown pass to Demaryius Thomas on the game’s opening drive and Danny Trevathan intercepted Philip Rivers and returned it 25 yards for a score to lead the Broncos to a 17-3 victory.

Osweiler was 16 of 26 for 166 yards as he moved to 3-0 since he took over for the injured Peyton Manning. The Broncos improved to 10-2 as they close in on their fifth straight AFC West crown.

San Diego fell to 3-9, taking its fifth straight home loss and its fifth straight against division foes. It was the Chargers’ second consecutive home game without a touchdown; they lost to AFC West rival Kansas City 33-3 on Nov. 22. It’s been more than a year since they’ve beaten a division foe.

Thousands of Broncos fans cheered the visitors in what might have been the penultimate Chargers game in San Diego. Chairman Dean Spanos wants to move to an industrial suburb of Los Angeles, and NFL Commissioner Roger Goodell last week warned San Diego that it had until the end of the month to come up with a solid plan for a new stadium.

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The Chargers walked away from stadium talks in mid-June.

With about five minutes left, Broncos fans cheered a scoreboard update showing Philadelphia leading New England. Osweiler helped lead the Broncos to a 30-24 overtime victory against New England last Sunday night.

The Broncos had no trouble moving 76 yards in eight plays on the opening drive, including a 22-yard run by C.J. Anderson and a 21-yard pass to Thomas. Osweiler then found Thomas wide open in the end zone for the score.

On San Diego’s third possession, Rivers was hit and the ball went straight to Trevathan. He rumbled in to make it 14-0. It was his first NFL score and the fifth defensive touchdown for the Broncos this season. He later left with a concussion.

It was Rivers’ fifth pick-six of the year. Rivers was 18 of 35 for 202 yards and was sacked four times. It was his second-lowest yardage of the season.

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The Broncos pushed it to 17-0 on Brandon McManus’ 23-yard field goal late in the second quarter.

San Diego rookie Josh Lambo kicked a 51-yard field goal just before halftime to avoid a shutout. He missed a 48-yarder in the first quarter.

Chargers receiver Dontrelle Inman suffered a scary injury in the first quarter. He was immobilized on a backboard and taken off the field on a cart after a helmet-to-helmet hit by Denver safety David Bruton Jr.

Inman was hit after making a 15-yard catch for a first down.

A few plays later, cornerback Brandon Flowers was hurt. He too was taken off the field on a cart.

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Running back Melvin Gordon, the Chargers’ first-round draft pick, lost another fumble and was benched. He has lost four of his five fumbles and has yet to score a touchdown.