– The top seed in the AFC playoffs belongs to Denver, along with a quarterback quandary.

Peyton Manning's stint as a backup didn't last long. He replaced Brock Osweiler in the third quarter Sunday and led the Broncos to a 27-20 victory over San Diego.

Broncos coach Gary Kubiak said he played a hunch, but he refused to reveal who will be his starter in the playoffs — or even acknowledge he has quite a puzzle at the position.

Osweiler threw for 232 yards, including a 72-yard TD pass to Demaryius Thomas on the game's second play. But he was victimized by five turnovers, including two interceptions that weren't his fault, and a fumble by Emmanuel Sanders at the 10-yard line after a 46-yard reception.

One of Osweiler's interceptions went off receiver Jordan Norwood's hands. His arm was hit by a linebacker on the other, and his day was done after a fumble by C.J. Anderson on the second play after halftime.

None of that was his fault, but the Broncos needed a spark and Manning, coming back from an injured left foot, provided it.

"I don't think Brock did anything wrong," Kubiak said. "I know we had the turnovers, but a couple of them he had nothing to do with. But just my gut told me to turn it over to [Manning] and let him lead the football team. I'm just very proud of him. He's worked really hard to stay there for us and it couldn't be a bigger day to be there for us."

Manning led Denver to 20 points in 1½ quarters despite going only 5-for-9 for 69 yards.

"It was tough on the emotions," Osweiler said. "But winning the AFC West is what it's all about."

Denver did that for the fifth consecutive time, staving off the Kansas City Chiefs, whose 23-17 victory over Oakland would have sent the Broncos (12-4) tumbling into the wild-card round with a loss to San Diego.

The Chargers (4-12) wrapped up what might have been their final season representing San Diego as ownership tries to move the team to L.A.

Manning's last scoring drive lasted one play: a 23-yard run by Ronnie Hillman after emergency safety Shiloh Keo, who surrendered Antonio Gates' go-ahead TD in the third quarter, picked off Philip Rivers' errant pass with just under five minutes remaining.

Rivers, for one, was surprised to see Osweiler get the hook.

"It wasn't like he was stinking it up out there," Rivers said. "But not surprised in the sense that you have a guy that hasn't been a backup in a game since '94 and is one of the best of all time."