ENGLEWOOD, Colo. — The Denver Broncos’ annual trip to San Diego started in a routine manner for quarterback Peyton Manning: flight, bus to the hotel, production meeting with the crew broadcasting the game.

About 6:30 p.m. Saturday night, as he met with offensive coordinator Adam Gase, that changed.

“He was in his bed and they were saying he was throwing up and all this,” said wide receiver Demaryius Thomas. “Everybody knew how sick he was.”

Added Manning: “I had a rough night. I’m not going to lie. It was not an enjoyable night. So I don’t know what happened, it just came out of nowhere.”

Manning took four IVs in the evening and morning that followed, got himself ready and completed 14 of 20 passes for 233 yards and a touchdown as the Broncos lurched past San Diego 22-10 to clinch their fourth consecutive AFC West title.

Thanks to the IVs, he muddled through. But there was no guarantee that he would play.

“If I felt like I was going to hurt the team by being out there, then obviously (I wouldn’t have played),” Manning said. “But I was kind of counting on Gase and (coach John) Fox and those guys to kind of look at me and evaluate me and kind of tell me what they thought as well.”

Piling on to Manning’s discomfort was the thigh injury he suffered as the Broncos drove toward their third field goal of the first half. He suffered the injury on an 8-yard pass to Emmanuel Sanders, two plays before he tried to block linebacker Donald Butler on running back C.J. Anderson’s unsuccessful attempt to score from the San Diego 1-yard-line.

Butler knocked Manning off-balance on the collision, but he paid a price: a dislocated elbow that ended his season. Meanwhile, Manning returned for the second half, completed six of his next eight passes for 96 yards — an average of 12.0 yards per attempt — and threw a 28-yard touchdown pass to Thomas.

“You can’t ask for (any) better,” Thomas said. “If a man comes out and plays that sick and throwing up and all this other stuff, that’s all you can ask for.”

REPORT CARD VS. CHARGERS

–PASSING OFFENSE: B-plus — Once again, the Broncos didn’t pass often, but Peyton Manning and his targets had one of their most efficient days of the season, Manning averaged 11.65 yards per attempt, the second-highest single-game figure of his three years with the Broncos, and threw for one more yard than Philip Rivers — in spite of having 21 fewer attempts.

–RUSHING OFFENSE: C-minus — The Broncos kept pounding, but yardage was hard to find, and running backs C.J. Anderson, Jeremy Stewart and Juwan Thompson combined to average just 3.29 yards per carry. Injuries to Ryan Clady and Paul Cornick did not help, because they left the two-tight end set with Virgil Green and Julius Thomas, and while Green did well in his blocking assignments, Thomas struggled.

–PASS DEFENSE: B-plus — The Broncos’ secondary had its best day of the season in downfield coverage, forcing Philip Rivers to take one checkdown after another. San Diego did not have one play longer than 20 yards, and their only success came on dump-off passes to their running backs, which accounted for four of their seven plays of more than 15 yards. Rivers averaged just 5.66 yards per attempt, his lowest average of the season.

–RUSH DEFENSE: A-minus — Terrance Knighton dominated his matchups on the inside, exposing the inexperience of San Diego’s rookie center, Chris Watt. The Chargers persisted at attempting to run, but the Broncos engulfed their ball-carriers, holding them to 2.8 yards per carry and allowing first downs on just 15 percent of their 20 carries.

–SPECIAL TEAMS: B — K Connor Barth has outscored three entire teams since signing with the Broncos, and has made all 11 of his field-goal attempts, including a 49-yarder that helped clinch the win Sunday. Kickoff specialist Brandon McManus continues to flourish in his specialist role, with touchbacks on five of seven kickoffs Sunday. But the Broncos committed a holding penalty on a fourth-quarter kickoff return and allowed Eddie Royal to dash 58 yards with a punt return that led directly to a Chargers field goal, and dropped Britton Colquitt’s net punting average to 20.0 yards Sunday.

–COACHING: B-plus — The ever-evolving Broncos had to adjust to the loss of both linebackers that had radio receivers in their helmets, which forced them to rely on verbal communication and hand signals in order to convey the calls. But even without the radios and the men who wore them, the defense responded without a hitch, intercepting two passes.