DENVER — A blizzard covered the Mile High City during the week, so maybe it's not too early in the NFL season to start talking about really significant games.

And Indianapolis at Denver is about as colossal as an October game can get.

"I love a game like this because it doesn't get any bigger," Broncos wide receiver Javon Walker said. "It reminds me of back in college with Florida State getting ready for Florida or Miami. It's a big game. It's going to be magnified. People are talking about it."

Despite some flaws on one side or the other, the Colts (6-0) and Broncos (5-1) are so good at what they do well that they're harkening to the league's formative days of leather helmets and two-way players.

The Colts can become the first team to start 7-0 in consecutive seasons since the 1929-31 Green Bay Packers, who did it three straight years. No one else has done it twice.

The Broncos have already made history, becoming the stingiest team to start a season since the 1934 Detroit Lions shut out their first seven opponents.

Denver has allowed just two oh-by-the-way touchdowns this season, both coming in the fourth quarter after they had built 17-0 leads on New England and Cleveland. They've held their last five opponents to single digits, a franchise best.

Broncos quarterback Jake Plummer, the biggest beneficiary of Denver's stifling defense, which has taken some heat off his season-long poor play, said this one feels like a playoff game.

"Any time you have an undefeated team coming to your place and we're 5-1, it's a big game," Plummer said. "(Winning it) sends a statement. It doesn't mean you're going to win the Super Bowl by any means, but it just sends a statement to everybody that you can beat the good ones, too."

Plummer's job got harder this week when left tackle Matt Lepsis was lost for the season with a knee injury, leaving Adam Meadows, Erik Pears or right guard Cooper Carlisle as candidates to face Colts star defensive end Dwight Freeney.

The Colts have their own injury issues, with defensive tackle Montae Reagor (eye socket) missing his second straight game and safety Mike Doss being placed on injured reserve with a torn knee ligament. The Colts expect to have Pro Bowl safety Bob Sanders (knee) back for the first time in a month.

The Colts are averaging 28 points; the Broncos are allowing just seven a game.

"We believe we can score on anybody, and I'm sure they like to believe they can stop anyone," Colts coach Tony Dungy said. "Everybody's going to focus on that matchup, but special teams, our defense against their offense is going to be just as critical."

What everyone really wants to see, however, is Indy's prolific offense going against Denver's dominant defense. Peyton Manning, Marvin Harrison, Reggie Wayne and Dallas Clark vs. Al Wilson, Champ Bailey, Darrent Williams, John Lynch and Ian Gold.

"They are just playing excellent fundamental defense right now," Manning said. "Their tackling is exceptional. That's one thing that just jumps out at you."

The Colts? Well, they're the same high-scoring bunch that's been tearing up the AFC for years.

"They are the best at what they do," said Denver defensive coordinator Larry Coyer.