ST. LOUIS -- Just like every week, Peyton Manning was the dominant topic in the opposing locker room. The decision making, the incessant barking under center that must be deciphered, the throws he just doesn't miss.

"I will say he's smarter than most quarterbacks," St. Louis Rams safety Mark Barron said. "The last time I played him we came away from the game thinking maybe he had cheated or something. Seriously."

"I think he has way too many code words," outside linebacker Jo-Lonn Dunbar added.

Given the state of their low-wattage offense, the Rams likely will need another big game from a pass rush that's piled up 16 sacks the last four games to keep it close against the AFC West-leading Denver Broncos.

"They've got really good players, a lot of first-round draft choices, guys that were great players in college that have made the transition to the NFL. All impact players," Manning said. "You've got to be able to try to control those guys somehow, and it falls on everybody."

Manning leads the NFL with 29 touchdown passes and is coming off his ninth career five-TD game, passing Drew Brees for most in league history. The Broncos' offense has been formidable, scoring 30-plus points in five of the last six games.

"I can't remember a time when he was playing any better," Rams coach Jeff Fisher said. "He's got great people around him, he's got a really good feel, he's not going to take the sack, he's not going to make the bad decision."

Denver (7-2) is stout defensively, too, ranked No. 1 against the run and fifth overall. The Rams (3-6) are 1-3 at home and have changed quarterbacks.

Things to watch for in Broncos-Rams:

• QB switch: Veteran Shaun Hill lost the Rams job when he missed two games with a thigh injury and neophyte Austin Davis stepped up, prompting Fisher to stick with the hot hand. A rapid-fire series of giveaways by Davis in a difficult fourth quarter turned a 14-10 lead at Arizona into a dispiriting 31-14 loss last week. Two days later, Fisher gave Davis a vote of confidence when he benched him in favor of Hill.

The Rams were 1 for 10 on third down last week. Fisher factored in a string of tough defenses as part of Davis' demise, and gave Hill no long-term guarantees.

"Obviously, the expectations and things like that don't need to be explained to me," Hill said. "I understand how it goes."

The 34-year-old Hill will try to reinvigorate an offense that's averaged 11 points the last three games, and the Broncos don't consider him an X factor.

"We have plenty of tape on him, preseason, in the past, whatnot," coach John Fox said. "Their offense doesn't change and they're a little similar in style."

• O-line shuffle: The Broncos replaced three of their offensive line starters last week, then put the Raiders away 41-17 on the road.

They brought in guard Richie Incognito for a workout this week and down the road could sign a player suspended last year for bullying a teammate while in Miami. "If we did sign him, he would have to adjust to our locker room," defensive tackle Terrance Knighton said. "We have a way that we do things here, and that starts at the top."

• Dangerous underdogs: Though the Rams have slid in Year 3 under Fisher, two of their victories are against NFC powers Seattle and San Francisco. Before the roof caved in last week, Arizona got a tussle.

"You can't take these guys lightly," Denver wide receiver Emmanuel Sanders said.

It's heartening yet frustrating for a team that hasn't had a winning record since 2003.

"We want to finish," said defensive end Chris Long, who has returned to practice from left ankle surgery after the opener, but most likely won't play this week. "It's not enough for us to just be in a game."

• Traveling band: This will be the Broncos' third straight road game, a stretch that began with a 43-21 loss at New England. They're 2-2 on the road and want to hit the ground running.

"However, if it doesn't happen, we like to think we can handle and make the necessary adjustments like we did last week, and eventually get on track," Manning said.

• Prolific pass catchers: With a combination of physical play and speed, Broncos wide receiver Demaryius Thomas has six consecutive 100-yard games, among eight players in NFL history to do it.

Julius Thomas is the first tight end in NFL history to catch 12 TD passes in consecutive seasons. He leads the NFL in TDs receiving, matching the most in league history after the first nine games.