On Sunday, viewers of the Broncos-Chargers game will be treated to the unusual sight of a healthy Peyton Manning standing on the sideline, serving as the backup quarterback. How unusual? It hasn’t happened since Sept. 24, 1994, when Manning was a freshman at Tennessee.

On that day — 7,770 days ago — the future NFL superstar was an 18-year-old Vols third-stringer, backing up a future MLB star, Todd Helton, who himself was filling in for injured starter Jerry Colquitt. Helton hurt his knee in that game, so Manning took the field, made his first start a week later and never again suited up as a reserve in a meaningful contest.

Until Sunday. Manning has recovered enough from his plantar fascia injury to have practiced fully this week and been activated for Denver’s regular season finale, but Brock Osweiler will be the Broncos’ starting quarterback.

In the six games Osweiler has started since Manning was shelved in mid-November, the first six starts of his four-year career, he has performed fairly well: a 61.7 completion percentage, 1,735 yards passing, nine touchdowns, four interceptions and an 87.3 rating. Compare that to Manning’s numbers in nine starts this season: a 59.9 completion percentage, 2,180 yards passing, nine touchdowns, 17 interceptions (still the most in the NFL) and a 67.6 rating.

Broncos Coach Gary Kubiak had previously indicated that when Manning returned to health, he would get his job back, but now Denver is in a situation where a win gets it the AFC West title, a first-round playoff bye and, if the Patriots lose, home-field advantage throughout the conference playoffs. Like most coaches facing a crucial game, Kubiak would rather go with what has been working, which is undoubtedly Osweiler.

“Obviously it means a lot,” Osweiler said Thursday (via the Associated Press). “It shows that Coach believes in me.”

Manning, true to form, has said all the right things about the situation, but what essentially constitutes a benching continues one of the more difficult stretches of his career. In addition to trying to come back from injury and dealing with his new-found status as a backup, the five-time NFL MVP has seen his sterling reputation besmirched by a report alleging that he used human growth hormone to help recover from multiple neck surgeries in 2011, which he vehemently disputed.

“The report wasn’t true Sunday. It’s not true today and it won’t ever be true,” Manning said Thursday (via the AP). “And I’m still angry about it. And if the league has to do [investigate], I’ll cooperate. The sooner the better, though, if they’re listening.”

What may not come as soon as Manning would probably like is his 187th career win, which would break a tie with Brett Favre for the most ever in the NFL. It is entirely possible that Manning has started his last game for the Broncos, and if he wants to regain first-string status, he may have to find a new club next season, when he’ll be 40.

After four years in Denver, the first three of which were extremely successful, following 13 record-setting campaigns in Indianapolis (not counting the 2011 season he essentially sat out), it would be odd to see Manning in a new uniform this fall. But then again, everything about the quarterback has already become highly unusual.