DENVER – The Broncos know there's only one way to erase "43-8" forever, and the path to that doesn't rest with their offense.
Denver knows what it has on offense. It's great. If the Peyton Manning-fueled machine suddenly breaks down, the Broncos aren't going to sniff anything special anyway. It's all on the defense.
If the defense is just good, maybe Denver can win a Super Bowl and forget all about that blowout loss to the Seahawks in last year's title game. The Broncos know that.
"When the offense is doing great, that's a great thing," safety Rahim Moore said. "To win in this league, you need a great quarterback and you need to put up points. But to win championships, you have to stop teams from scoring."
When the Broncos were up 24-0 in Sunday night's season opener against the Colts, on their way to a 31-24 season-opening win, the defense looked more than just good. It was dominant. But then all of a sudden it was the loss to Seattle all over again, with receivers running around and through the defense. Colts quarterback Andrew Luck, who finished with 370 passing yards, was in Broncos territory late in the fourth quarter trailing by a touchdown with a chance to at least send the game to overtime. This is the kind of collapse that shouldn't happen to a team with championship aspirations. The Broncos held, with rookie cornerback Bradley Roby knocking away a fourth-down pass just inside of the two-minute warning, but what in the heck was that?
"We just wanted to make it interesting," defensive lineman Terrance Knighton said with a grin. "We didn't want fans to leave or anything."
Let's start with Denver's good news. In the first half, when Denver led by 24 with 1:57 remaining, the Colts had 57 yards and four first downs. Indianapolis' running game was doing nothing and Luck was under consistent pressure. It's easy to forget but here are the Broncos defenders who didn't play in last year's Super Bowl: cornerbacks Roby, Chris Harris and Aqib Talib, safeties T.J. Ward, Quinton Carter and Rahim Moore, outside linebackers Von Miller and DeMarcus Ware and defensive end Derek Wolfe. This defense is entirely different, and much more talented. It showed early on against the Colts.
"Everybody was playing fast," linebacker Brandon Marshall said. "Everybody was giving perfect effort .The D-line was getting penetration. The secondary was locking down. The linebackers were flying around making plays."
And there were some good moments after halftime. Early in the second half, the Broncos had a tremendous goal-line stand. Hakeem Nicks was stopped just short of the goal line on third down by Roby and Carter. Then Luck tried hurrying to the line for a quarterback sneak on fourth and goal, but Knighton pushed the interior of the line back, stopping Luck cold, and Marshall finished it off with a tackle. By the end of the game, that stand turned out to be huge.

And if that's really the Broncos' defense – the defensive line holding up, the pass rush coming off the edge and the secondary making big plays – start making plans for Denver's repeat trip to the Super Bowl.
But then what do you make of the Colts marching down the field in the second half? There was a common theme among the Broncos.
"Andrew Luck is known to do that," Marshall said. "You saw what he did in the playoffs."
"You can never think [it's over], especially with a guy like Luck back there," Roby said.
"Playing against a great guy like Andrew Luck, and the way he plays, he's going to score points," Ware said.
And unquestionably, when Luck got it going he made some tremendous throws. And it's not unusual to let up some with a huge lead, which the Broncos had at 24-0 and 31-10. That doesn't explain everything. The Broncos looked like a different defense in the second half. Maybe it was that players like Harris and Miller were limited on their snaps in their first regular-season games back from knee injuries. Miller said he still needs to get into football shape to play a full game, but he did say his knee felt good.

No matter the reasons, the Broncos gave up 351 yards in the final 32 minutes. That will get you beat when it matters.
"We feel like we played good enough," said Ware, who looked good in his Broncos debut with 1.5 sacks. "But there's room for improvement."
So which is the real Broncos defense? The one swarming Luck and making it impossible for the Colts to get first downs? Or the one that kept giving up big plays and almost let the Colts pull off what would have been a devastating comeback?
The ultimate answer will likely determine if the Broncos can erase last season's Super Bowl nightmare and take the next step this season.
"This is the first game, we have a long way to go," Marshall said. "We'll keep getting better. We'll be a great defense, definitely."
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Frank Schwab is the editor of Shutdown Corner on Yahoo Sports. Have a tip? Email him at [email protected] or follow him on Twitter! Follow @YahooSchwab