Or it could be Brock Osweiler.
Would either decision really come as a surprise for the Broncos, whose 27-20 victory over the Chargers fit the script of their season - by being anything but routine?
A recap of Sunday's madness:
- Manning came off the bench to trigger a come-from-behind win, yet only completed five passes for 69 yards.
- Osweiler started and threw for 232 yards, including a 72-yard touchdown, and got pulled even though his coach conceded the quarterback did nothing wrong.
- Denver had five giveaways and became the first team since 2012 to win despite going minus-4 in turnovers.
- The Broncos (12-4) earned home-field advantage in the AFC less than two weeks after heading into their 15th game on a two-game losing streak and two games behind New England.
''It's been,'' Manning said, ''a pretty different year.''
Coach Gary Kubiak shifted the momentum with his decision to pull Osweiler early in the third quarter, after C.J. Anderson lost a fumble for Denver's fifth turnover. That one wasn't Osweiler's fault. And it could be argued that his two interceptions, one of which hit receiver Jordan Norwood in the hands before being picked, weren't either.
''I don't think Brock did anything wrong,'' Kubiak said.
Not surprisingly, the coach declined to say who would start at quarterback when the Broncos, now winners of five straight AFC West titles, play on Jan. 17 in the second round of the playoffs.
He said he felt totally comfortable giving the 39-year-old Manning his first action since Nov. 15, when No. 18 left a four-interception game against the Chiefs with a torn tendon in his left foot.
Asked about Manning's strange and still-evolving season, Kubiak said, ''He's the ultimate professional. It's been a little weird here for me, too.''
After his first career victory in relief, Manning was hardly ready to take credit for the win. Denver didn't commit a turnover during his six drives. The running game amassed 139 yards while Manning was in, compared to 71 for Osweiler.
''I can't take credit for having a really good handoff and helping those guys hold onto the ball,'' Manning said.
Things we learned from Sunday's game:
THE OTHER REPLACEMENT: Manning entered the game at about the same time as backup right tackle Tyler Polumbus, who replaced the struggling Michael Schofield. It was Schofield who let Khalil Mack of the Raiders do most of his damage last month during Mack's five-sack game. With Polumbus in, running backs Ronnie Hillman (117 yards) and Anderson (95) did most of their damage, including Hillman's 23-yard burst for the winning score.
GOODBYE CHARGERS: It may have been their last game as the San Diego Chargers. They are one of three teams, along with the Raiders and Rams, who could be moving to Los Angeles next year. This was a lost season - one in which Philip Rivers finished with 4,792 yards, only 10 short of the team's single-season passing record (Dan Fouts), but the Chargers only mustered four wins. ''When it's all said and done,'' said 13th-year tight end Antonio Gates, ''we've got to try to win more football games. That's what I concern myself with.'' And FYI, the Chargers will pick third in next season's draft.
OSWEILER SAYS: Osweiler keeps a checklist on a little card in his locker on game days. ''Ball security'' is near the top of the list. Though it could be argued that none of Denver's five turnovers were his fault, Osweiler didn't see it that way. ''I'm always going to point the finger at myself,'' he said.
COACH McCOY: Unlike other bad teams (read Cleveland, Philadelphia, San Francisco) who made quick coaching moves, the Chargers stayed mum on the future of Mike McCoy. His status is trickier in large part because the Chargers are also dealing with the potential move to Los Angeles. Asked about his standing after Sunday's game, McCoy said: ''I'm the head football coach until they tell me different.''
TOP-SEED TO SUPER BOWL: This is the eighth time the Broncos have earned the No. 1 seed in the AFC. Of the previous seven, they've been to the Super Bowl five times and lost their first game twice, including in 2012 to Baltimore.
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