The 8-0 Kansas City Chiefs have some big games upcoming, including showdowns for AFC West supremacy on Nov. 17 and Dec. 1 against the Denver Broncos. But first is Sunday’s game against the 3-5 Bills in Buffalo.

ESPN Chiefs reporter Adam Teicher and Bills reporter Mike Rodak discuss the game:

Teicher: With the exception of three lost fumbles, it looks like quarterback Thad Lewis is playing better than the Bills had a right to expect. For those of us who aren't familiar with his game, give us a little scouting report with regard to his strengths and weaknesses and things he might be able to do -- if he is able to play Sunday -- that could give the Chiefs some trouble.

Rodak: I think you nailed it. Even though Lewis is still in the bottom third of the league among quarterbacks, the Bills are more than happy with what they're getting from him. Most importantly, Lewis is a heady player with a real strong grasp of the offense. That's what impressed offensive coordinator Nate Hackett when they sat down with Lewis after EJ Manuel's injury and why they chose him. He's physically not the most gifted quarterback, but Hackett likes Lewis' arm strength. We've seen it on some deeper passes Lewis has completed in the past three games, and if he can get the protection, they're going to keep trying that. As a runner, Lewis isn't Terrelle Pryor, but he has the mobility to run the read-option the Bills like to mix in out of their no-huddle offense. The question is, how much will they run him? Lewis got drilled from behind on a designed run to begin the game Sunday, suffering bruised ribs, and his status against the Chiefs is still up in the air. If Lewis plays Sunday, the Chiefs shouldn't have to worry too much about him as a runner.

Adam, I'm sure you've been asked this plenty of times this season, but what has clicked for the Chiefs? Was it the move away from Scott Pioli and Todd Haley/Romeo Crennel to John Dorsey and Andy Reid, or were there personnel changes that made a bigger impact?

Teicher: The coaching and administration moves were huge. For the previous four seasons the Chiefs had a lot of guys with their own agendas, pulling in different directions and focusing on things that didn’t matter. Dorsey and Reid deserve a lot of credit for getting everyone to fall in line behind them. Everyone has the same goals now. Reid has persuaded some players to put aside personal goals for the greater good. A lot of Chiefs players were tired of the losing and the sideshow stuff and were ready to be led in a positive direction. Reid walked through the doors with some impressive credentials and they listened to him. As far as personnel changes, most of the Chiefs' better players are ones who were here when Reid and Dorsey arrived. The only new guy in what you could call a key role is QB Alex Smith. Otherwise, most of their key players (Jamaal Charles, Branden Albert, Dontari Poe, Tamba Hali, Justin Houston, Derrick Johnson and Eric Berry) have been around.

Smith was sacked six times against Cleveland last week and 24 times this season, so pass protection has been a problem for the Chiefs. The Bills are doing a good job getting after the opposing quarterback. What have teams done to try to counter Mario Williams, and do the Bills have anyone else consistently putting pressure on the quarterback?

Rodak: I think the best job an opposing offense has done against Mario Williams was in Week 6, when the Bengals took down the Bills in overtime. They caught the Bills off guard by opting for a shorter passing game, forgoing the chance to attack a shaky (at the time) Bills secondary with A.J. Green. Instead, Marvin Jones had a 34-yard end-around run and a 42-yard catch-and-run in the first seven minutes of the game that set the tone. Williams finished with just one tackle and a half-sack, even with the extra period. The Bills don’t have a player putting up 11 sacks like Williams, but their pair of defensive tackles -- Kyle Williams and Marcell Dareus -- are among the better duos in the league. Each has four sacks. Overall, Mike Pettine’s defense thrives on generating pressure from many different sources, including the defensive backs. Andy Reid is a veteran coach and knows his offense will have to be ready for the blitz from start to finish Sunday.

Adam, would you say the Chiefs are effective in spite of Alex Smith this season -- he has posted just an 82.1 QB rating -- or because of him? Is their success through the first half of the season sustainable even with Smith at quarterback?

Teicher: There are things Smith can be doing better, but they’re 8-0 because of him, not in spite of him. Among the things Smith has done exceedingly well are protect the ball and run from trouble. Smith has thrown only four interceptions, so he’s not forcing the ball into tight situations or otherwise taking risks with it. He’s fumbled just once, and the Chiefs even recovered on that one. For him to handle the ball on every offensive play and have only four turnovers is amazing. When he’s been sacked, he’s holding on to the ball. Smith is the Chiefs’ second-leading rusher and has scrambled out of trouble a number of times. It’s fair to say they wouldn’t be 8-0 without his running ability. It’s been that valuable. That said, Smith needs to complete a higher percentage of his passes. Right now, he’s only at about 59 percent. Getting that into the low to mid 60s would make a big difference for the passing game. The Chiefs also have trouble getting touchdowns in the red zone. That can’t all be blamed on Smith, but he can be more efficient inside the 20.

I can’t figure out why the Bills aren’t better defensively. They’ve been solid against the run, have strong pass-rush capability, create a good number of turnovers, yet still have allowed 20 or more points in every game. I know they’ve allowed some big pass plays. Is that the only reason they haven’t been better defensively?

Rodak: I think the big plays are part of it, Adam. The Bills have allowed 14 receptions of 35 yards or more, the most in the NFL. But the Chiefs have allowed 12, the second-most, so there’s more to it than that. I think the first place to look is on the other side of the ball, where the Bills' offense averages just 27:41 in time of possession. That’s the fourth-lowest mark in the league and is putting stress on the defense. The Bills have a creative mind in defensive coordinator Mike Pettine and talent at all three levels of their defense. But their offense, between injuries and inexperience, has been so ineffective at some stretches that the defense just can’t hold up. This is a defense that has put pressure on opposing quarterbacks and forced some turnovers, but they’ll need to prevent the big play and have their offense pick up some slack going forward.

Adam, what do you think it will take for the Chiefs to lose Sunday?

Teicher: Opponents have started to give the Chiefs their best shots. Houston did two weeks ago and Cleveland did last week, and each team came close to knocking off the Chiefs at Arrowhead Stadium. So if the Texans and Browns can keep things close in Kansas City, it reasons that the Bills can beat them in Buffalo. The Chiefs have played the past couple of weeks, and particularly against Cleveland, as if they’re weary of the burden of being the NFL’s remaining unbeaten team. They took a 13-0 lead against the Browns, then looked like they ran out of energy. They’ll need to bring more Sunday in Buffalo or they certainly could be in trouble. The Bills could make things easier on themselves by getting an early lead. The Chiefs have led much of the time this season and have been able to play the games on their terms. When they’ve been behind, it’s never been by more than a touchdown. Kansas City has trailed in the fourth quarter in just one game, that being by four points early in the final period on Oct. 6 in Tennessee. That deficit didn’t last long, so it would be interesting to see how they do if they need to play catch-up late in a game.

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