The Broncos look to remain undefeated on Sunday when they visit the stumbling Kansas City Chiefs, who try to avoid extending their franchise-record losing streak to 13 games.

Denver (3-0) is one of six undefeated teams in the NFL, but it hasn't been easy.

After making a 2-point conversion in the final seconds to beat San Diego 39-38 on Sept. 14, the Broncos escaped with a 34-32 win over New Orleans last Sunday when Martin Gramatica's 43-yard field goal try with 1:55 remaining was wide right. It was the second straight week Denver led 21-3 only to barely hang on.

"We've got to be the luckiest team right now because of what's going on," cornerback Champ Bailey said. "We put ourselves in those situations, but right at the end things have been happening for us. You've got to take it as a good sign."

Denver, which is 3-0 for the first time since opening the 2003 season with four consecutive victories, has been led by an offense that averages a league-best 38.0 points and is second in total offense (435.0 yards per game).

Jay Cutler has emerged as one of the top quarterbacks in the NFL, throwing for 914 yards, eight touchdowns and two interceptions. Cutler and Brandon Marshall are also creating one of the top quarterback-wide receiver tandems in the league. Marshall, who was suspended for the season opener for violating the NFL's personal conduct policy, already has 24 catches for 321 yards and two touchdowns.

While Denver's offense is surging, the defense has been susceptible.

The Broncos have allowed the third-most yards in the league (432.0) and the fifth-most points (28.0). In their last two games, they've given up 70 points and 958 yards.

"It's nice to give up 32 points and still win the football game," Denver coach Mike Shanahan said after last Sunday's victory. "That's the bottom line, you've got to find a way to win.

"I think our guys are realistic: We have a ways to go. We've had a good start, we've made some strides, but we're far from where we want to be."

The last two quarterbacks the Broncos faced - San Diego's Philip Rivers and New Orleans' Drew Brees - picked Denver's secondary apart for 798 yards, but things should be different on Sunday.

After starting three quarterbacks in their first three games, Damon Huard will make his second start of the season for the Chiefs (0-3).

Huard takes over for Tyler Thigpen, who threw three interceptions in his first career start in last Sunday's 38-14 loss to Atlanta.

Huard, who is 10-for-16 for 135 yards with a touchdown and two interceptions, again gets to direct one of the worst offenses in the league. The Chiefs rank fifth-worst in total yards (282.7) and have scored the third-fewest points (10.7).

Their defense isn't any better, as they are 24th in scoring (26.0) and 25th in total defense (362.3).

"We don't have a strength right now on either side of the ball," Kansas City coach Herm Edwards said. "You can't combat it with something. Generally, you can lean on your strength, but right now we don't have a strength. We're not really strong in any area right now.

"It's not fun right now for anybody. It's not fun for the players, the coaches, the fans. But it's the road we're traveling and now it's our job to try to get better every week."

The Chiefs, who have not won since defeating Oakland 12-10 last Oct. 21, are trying to avoid starting 0-4 for the first time since 1980.

Kansas City's 12-game losing streak includes two defeats to Denver last season, as the Broncos outscored the Chiefs 68-18 in those games. Denver's 27-11 win at Arrowhead Stadium on Nov. 11 snapped a four-game losing streak at Kansas City.

Cutler threw for 436 yards, five touchdowns and one interception in 2007 against the Chiefs, while Marshall had 16 receptions for 200 yards and two touchdowns. Running back Selvin Young, who has run for 179 yards this season, rushed for 265 and one TD on 37 attempts in the two games against Kansas City as a rookie last season.