HOUSTON -- With less than five minutes remaining in the fourth quarter and the Broncos leading a 2-12 team by 17 points, they emptied the backfield as Peyton Manning called the signals.

But this was not a breach of the unwritten rules of sporting etiquette about not embarrassing an opponent. The game was won, but every onlooker at Reliant Stadium knew what was afoot: history, and a moment that shaped how a team and a quarterback will go down in history.

"Everybody was like, 'Why aren't we running the ball? Why aren't we running the ball?'" said safety Mike Adams. "I'm like, 'Yo, the record, baby. The record.'"

The record. The single-season touchdown pass record.

Dan Marino raised the bar to 48 in a 1984 campaign that was decades ahead of its time; It took two decades until it was finally trumped, by Manning in 2004. Now the standard has been raised twice in the last seven seasons: by Tom Brady, who took it to 50 in 2007, and now by Manning, who has it at 51 -- and counting.

And while Manning's record-breaking touchdown pass to Julius Thomas out of that empty-backfield formation was the dominant image from Sunday's 37-13 romp at Reliant Stadium, there's a good chance that the football used won't be the one that becomes the most cherished object of his signature season.

Not with the Broncos still fighting for the No. 1 seed in the playoffs, needing a win next week to avoid a potential return trip to Foxborough, Mass. in January. Not with one more game in which Manning is set to put in a full Sunday's work.

Fifty-one? If Manning maintains his pace of 3.4 touchdowns per game, he could shatter Brady's mark. Fifty-four or 55 touchdowns seemed unfathomable at one point, and could be Manning's reality with nothing more than a typical game in his extraordinary season.

Nevertheless, he doesn't think that his record will end up enduring -- no matter what it is.

"I personally think all season records are going down – especially if they go to (a season length of) 18 games and there won't be an asterisk next to them," Manning said. "Brady will probably break it again next year, if not the year after."

"I'm sure it's just a temporary record. But I will enjoy it during this time."

The pass that assured he will hold the standard, even for a brief moment, was like almost any other pass in this, the best season of what could end up being the most prolific career any quarterback has ever enjoyed: it was defined by Manning treating his potential targets as equals, and choosing the man most likely to make the reception, based on his own skill, the separation from defenders and the risk-reward ratio.

All of these variables are analyzed in Manning's meticulous mind, which appears to be blessed with organic processors that are the envy of a top-of-the-line computer.

"You guys always say, 'Were you the primary read?' We don't have those, man," Thomas said. "We just all run around and Peyton will find the guy that's open."

It's a simple, but accurate explanation. It's why he's also on pace to set the league's single-season passing-yardage record, although that does not have the same meaning to Manning as the touchdown mark. Manning simply finds the open receiver who is capable of making the biggest play on that snap more often and better than anyone else in the sport today, and perhaps ever.

It happens so often, it can appear to the untrained eye to be hum-drum, even though so much goes on with each play that Thomas didn't know he was catching the record-breaking touchdown when he grabbed it.

So when he scored, he let go of the football, and Eric Decker, who had the record-tying touchdown, picked up the prized memento.

"I think I dropped the ball so fast, doing my usual thing, and Deck picked it up," said Thomas. "I was like, 'Why did Deck pick that ball up so fast?' I'm not paying any attention, I come back to the sidelines, I'm sitting down on the bench and somebody was like, 'That was the one!' I said, 'Ugh. Maybe I shouldn't have just dropped it so carelessly. I should've kept it!'"

But even if he had known, he wouldn't have hung onto it.

"I wasn't planning on keeping any more for the rest of the season," Thomas said. "It'll look better on Peyton's museum wall of accomplishments."

It's a wall that likely isn't complete, not with so many more goals still at stake: home-field advantage, a second consecutive 13-3 season, playoff wins and a Super Bowl.

The touchdown record -- whatever it may be -- is another line on a staggering resume that breaks the one-page rule for such documents. At this point, Manning's is more like a novella. But it's one that the he and the Broncos has chapters left to be written -- none of which involving toppling league records.

The records he has and can set are meaningful. But for him, they are a means to an end. No matter the time on the clock, he'll keep guiding the offense, keep reading the defenses, and when the looks are right, he'll keep throwing, pushing for more, more, ever more, until a trophy in his hand tells him, "You've done enough."

And that hasn't happened yet.