The San Diego Chargers held off the Denver Broncos for a 21-13 victory at Qualcomm Stadium.
Broncos coach Gary Kubiak was not at the game because of migraines and special teams coordinator Joe DeCamillis served as Denver's interim head coach on Thursday.
The Broncos were plagued by 12 penalties for 103 yards. The most crucial penalty was a holding call -- the fifth of the night -- that negated a C.J. Anderson touchdown that would have made it a one-score game with just over four minutes remaining.
San Diego harassed second-year quarterback Trevor Siemian most of the night with rookie defensive end Joey Bosa providing most of the pressure.
Siemian finished 30 of 50 for 230 yards and a touchdown.
Chargers quarterback Philip Rivers threw for 178 yards and passed Hall of Famer Dan Fouts as the franchise's all-time passing leader.
San Diego had been very good in the first halves of games this season, but the second half had been a different story. The Chargers had lost four games by a total of 14 points with each defeat coming after they held a second-half lead.
The Chargers had also not had much recent success within their own division and especially against the Broncos. The Chargers had lost 10 straight games to AFC West opponents and dropped nine of their last 10 games with the Broncos. The Broncos had not lost an AFC West road game since 2010, a span of 15 outings.
Melvin Gordon has finally started to look like the running back the Chargers hoped he would be when they selected him with the 15th overall pick of the 2015 NFL Draft. He finished with 94 yards on 27 carries and his 48-yard run in the third quarter was a career long and set up a 21-yard Josh Lambo field goal.
Hunter Henry, a second-round pick in April, had the best game of his young career with six catches for 83 yards. Rivers and Henry got the Chargers on the board with a five-yard touchdown pass to cap the opening drive.
"I was afraid we were going to find another way [to lose]," Rivers told CBS Sports. "We finally won a division game. We found a way to win.
"Winning a division game is big."
WORK TO DO
The Chargers took a step toward salvaging their season, but still have plenty of room for improvement. Thursday's game should not have been close, but stalled drives in the red zone and another lacklustre fourth quarter did little to build much confidence in Chargers coach Mike McCoy.
The Broncos, on the other hand, lost for the second straight time after opening the season with four straight victories. Denver have to use their extra time to regroup before a Monday game against the Houston Texans.