Alex Smith

Kansas City quarterback Alex Smith will look to keep the Chiefs undefeated on the season when they travel to Denver to take on the Broncos in an AFC West showdown on Sunday. (Bill Wippert / Associated Press / November 3, 2013)

The Kansas City Chiefs are 9-0 and the NFL's only undefeated team.

But how good are they, really?

We'll know a lot more Sunday when the Chiefs play at Denver in a pivotal AFC West showdown.

None of the teams the Chiefs have beaten have a winning record, but the Broncos are 8-1 and have Peyton Manning, who is in good position to win an unprecedented fifth most-valuable-player award.

Manning took a physical beating in Sunday's victory at San Diego and had an MRI exam on his sore right ankle Monday, but the examination revealed no new damage. He will start against the Chiefs.

"I'm pretty sore," Manning said Sunday. "They kind of got me twice in kind of that lower area."

Interim Denver Coach Jack Del Rio said Monday the Broncos sent those low hits to the league for clarification.

"We turned it in, thought it was questionable and they'll provide their answer," Del Rio said. "Of course, I won't share that with you, but that's just part of it. There are a number of plays throughout the game that you put in there and ask for clarification — that's one of them that we'll be looking for."

The Chiefs had Week 10 off, and Coach Andy Reid gave his players a break from practices. That's not to say they checked out entirely, though.

Said quarterback Alex Smith: "I think every guy in this locker room, in the back of their head [was] thinking about Denver."

Broncos cornerback Chris Harris said Monday that he expects Smith to play it safe and try to chip away at Denver's defense, rather than look for big plays.

"He's definitely a guy that, he doesn't want to make mistakes," Harris said. "He doesn't want to put their team in bad situations — kind of how [San Diego Chargers quarterback] Philip [Rivers] played yesterday. He kind of took the short pass, didn't really want to take a lot of shots. That's the kind of guy — people's game plan versus us now is to try and keep Peyton off the field."

State of shock

Indianapolis plays at Tennessee on Thursday night, and who would have dreamed both teams would be coming off losses?

The Colts were crushed by St. Louis, 38-8, and the Titans became the first team this season to lose to Jacksonville, falling at home, 29-27.

If the feeling of losing to the league's worst team is familiar to the Titans, it's because they lost to the 0-13 Colts two years ago.

"We've been part of this crap for the last three years — two years ago against the Colts, then the Jags last year and the Jags today," Tennessee tackle Michael Roos told reporters Sunday. "I don't know if guys think it's just gonna happen because of their record, but every Sunday there is an NFL you're playing in, despite what their record is."

The Colts still have a two-game lead in the AFC South, but they weren't making excuses after being pounded by the Rams.

"Certainly we're not going to bury our head in the sand on this past ballgame," Coach Chuck Pagano said Monday. "We'll address the issues like we always address them. We know there's things that need to be fixed and we'll go to work on fixing those things. Again, we have a short week. We don't have much time in front of us."

Quick return