"It's a big game," Broncos quarterback Jay Cutler said Wednesday as preparation began for a contest Sunday against the visiting Buffalo Bills that would vault Denver into the playoffs with a victory.

"Everyone in the locker room understands that. Everyone in the building, for that matter, understands that."

And everyone affiliated with the Broncos knows this, too: If Denver is going to succeed where it failed Sunday in its bid to clinch a postseason berth, it's up to Cutler to lead the way.

A team can thrive without stellar quarterback play if it has a dominant defense, a top-tier running game and/or plays relatively mistake-free.

The Broncos (8-6) have demonstrated none of those qualities on a regular basis.

As Cutler has gone, so have the Broncos. It's as simple as that.

"Yeah," coach Mike Shanahan conceded. "Pretty much."

In the Broncos' eight victories, Cutler has had at least a 61.8 percent completion rate in every game except Nov. 7 at Cleveland, when he threw for a season-high 447 yards. He also has had all five of his 100-plus quarterback ratings and none lower than 93.3 in wins.

The half-dozen losses have included his four lowest-yardage games and only one quarterback rating higher than 75, against Jacksonville on Oct. 12. Only one of his seven passes of more than 40 yards has come in the six losses, as have 18 of 26 throws of 25-plus yards.

Overall, Cutler is 198-of-294 for 2,447 yards with 17 touchdowns and five interceptions in the wins; 128-of-228 for 1,404 yards with seven touchdowns and 10 interceptions in the losses.

"You look at what you have," Shanahan said. "We've lost a number of running backs. Our running game isn't the same as it has been, for obvious reasons. We've had a running game at times, and we always stress the running game. You can't be one-dimensional. But it does put a lot of pressure on the quarterback, no question about it."

The Broncos rank 16th on the ground at 113.6 yards per game and are down to three tailbacks, two of whom joined the roster after the start of the season.

But a defense that is 28th in yards allowed (373.4), 29th in points allowed per game (26.1) and 32nd in takeaways (13) has only made it harder on Cutler.

Minnesota can overcome spotty play from Gus Frerotte and Tavaris Jackson and ride Adrian Peterson and a stout run defense.

Baltimore is ranked second against the pass and third against the run, allowing the Ravens to play conservatively with rookie quarterback Joe Flacco.

Tennessee's Kerry Collins has one of the lowest ratings in the NFL as a passer, but his 1.8 interception percentage is among the league's best.

And LenDale White and Chris Johnson have combined for 1,852 yards and 15 touchdowns, with a defense that has forced 27 takeaways.

In Denver, it's move it or lose it.

"Any team, anyplace, in any sport, anytime, when one guy touches the ball the majority of the time, the majority of the time you win or lose off his play - basketball with the point guard, baseball with the pitcher, stuff like that," Broncos receiver Darrell Jackson said. "Jay's handled it well. We're 8-6, still leading our division by a game. And we still have a chance to win the Super Bowl.

"There was a lot of pressure on him coming into this year anyway, with us not making the playoffs last year. So he's done a good job, especially with his own problems, with the diabetes and all that."

At Carolina on Sunday, the Broncos put up their second-fewest total of yards (279) and first downs (15) and the fewest number of net passing yards (158).

It was the second time in Cutler's career he has been at the helm in a game the Broncos needed to win to clinch a playoff berth - and the second loss.

The first came on Dec. 31, 2006, at Invesco Field at Mile High, with the Broncos hosting San Francisco, a team, like the Bills, that already was out of the postseason picture.

Cutler exited briefly with a concussion and finished 21-of-32 for 230 yards and a touchdown, plus an interception returned for a score, as the 49ers won in overtime.

"That was a totally different feel for me," Cutler said. "And I think it was a totally different feel for everyone in the locker room. We've got a totally different team. We've got more experience and I think a lot more confidence than we did in ourselves - and in me."

That loss the 49ers two years ago was only Cutler's fifth career start, so he largely was insulated from criticism.

He made his first Pro Bowl on Tuesday as his second full season as the Broncos' No. 1 quarterback winds down, so expectations are higher now.

"Each game I feel pressure. This game is obviously more important. The stakes are a little higher," Cutler said. "But I'm not going to change anything. I'm going to keep playing like I have all year and keep preparing like I have."

INFOBOX

Split decisions

The Broncos have yet to overcome a pedestrian effort by quarterback Jay Cutler this season. When he's on, the Broncos are successful across the board.

CUTLER VICTORIES Date Opponent Com Att Yds Pct. TD Int Rating

Sept. 8 at Oakland 16 24 300 66.7 2 0 137.5

Sept. 14 San Diego 36 50 350 72.0 4 1 109.6

Sept. 21 New Orleans 21 34 264 61.8 2 1 93.3

Oct. 5 Tampa Bay 23 34 227 67.6 1 0 96.1

Nov. 6 at Cleveland 24 42 447 57.1 3 1 107.9

Nov. 16 at Atlanta 19 27 216 70.4 1 0 106.4

Nov. 30 at N.Y. Jets 27 43 357 62.8 2 1 94.8

Dec. 7 Kansas City 32 40 286 80.0 2 1 102.7

CUTLER LOSSES Date Opponent Com Att Yds Pct. TD Int Rating

Sept. 28 at Kansas City 29 49 361 59.2 1 2 71.9

Oct. 12 Jacksonville 21 37 192 56.8 2 1 77.8

Oct. 20 at New England 17 26 168 65.4 1 2 64.3

Nov. 2 Miami 24 46 307 52.2 2 3 60.7

Nov. 23 Oakland 16 37 204 43.2 0 1 49.8

Dec. 14 at Carolina 21 33 172 63.6 1 1 74.3