* Defense sparks team's ninth win
* Smith returns interception 100 yards
The Kansas City defense came to the rescue scoring two touchdowns to secure a 23-13 victory over Buffalo Bills on Sunday as the Chiefs remained the National Football League's only unbeaten team.
With the win the surprising Chiefs, who finished tied for the league's worst record (2-14) a year ago, improved to a perfect 9-0, setting up a mouth-watering showdown in two weeks with AFC West rivals the Denver Broncos.
On an afternoon when the Chiefs' offense could muster only three Ryan Succop field goals their top-ranked defense took charge, Sean Smith returning an interception 100 yards for a touchdown and Tamba Hali scooping up a Buffalo fumble for another score.
"Every win you get in the National Football League is a good win," Chiefs coach Andy Reid told reporters. "We rallied in the fourth quarter and did some things that were better than we had done earlier.
"However the two touchdowns were very important.
"We were out-gained by a ton but the turnovers and the score are kind of the important things."
The Chiefs have found it easier to win games than win respect, critics dismissing their perfect mark as the result of a weak schedule.
But only 15 team have won their first eight games since the NFL expanded to a 16-game schedule in 1978 and nine of those made it all the way to the Super Bowl, eight of them walking away with the Vince Lombardi trophy.
Proving there are no gimmees in the NFL, the Bills, down to Jeff Tuel, their third string quarterback after injuries to number one E.J. Manuel and backup Thad Lewis, gave the Chiefs all they could handle on a sunny, brisk afternoon at a rocking Ralph Wilson Stadium.
They battled to a 13-13 draw heading into the final quarter, but hopes of an upset faded when Bills receiver T.J. Graham fumbled the ball on his own 11 and Hali returned it to the end zone to give the Chiefs their first lead of the day.
"It hurts me, it hurts the guys in that room, I hurt for them, I hurt for our fans," said Bills coach Doug Marrone after watching his team's record fall to 3-6. "It's tough. It's a tough one.
"I thought that there were a lot of good things that happened on that field today.
"Defensively, they did a heck of a job. We knew coming in that this team scored a lot of points off turnovers."
Chiefs quarterback Alex Smith delivered another steady but unspectacular effort completing 19-of-29 passes for 124 yards without an interception or a touchdown.
Tuel struggled in his first start, connecting on 18-of-39 passes for 229 yards and had a hand in the two of the biggest plays of the day as he hooked up with Marquise Goodwin on a pin-point 59 yard touchdown pass to give Buffalo the early 7-0 lead.
But the rookie quarterback was also intercepted twice, the most damaging coming early in the third quarter when Smith stepped in front of a one-yard pass attempt and returned the ball the length of the field for a score.
"So surprised, it was like Christmas, you go downstairs as a little kid and there is a box right there," said Smith. "That's how I felt.
"The main thing I wanted to do was just focus and catch the ball because I knew once I caught it no one was going to catch me."