Chiefs 23, Bills 13: Linebacker Tamba Hali celebrated his 30th birthday by returning a fumble 11 yards for the go-ahead touchdown early in the fourth quarter as visiting Kansas City benefited from a pair of standout defensive plays to improve to 9-0 for the first time in 10 years.

Cornerback Sean Smith returned an interception 100 yards for a touchdown and Jamaal Charles rushed for 90 yards. Dwayne Bowe reeled in a season-high seven catches for 67 yards for the Chiefs, who head into their bye week before visiting Denver in a key AFC West showdown on Nov. 17.

C.J. Spiller overcame the effects of a lingering high-ankle sprain to gain 116 of Buffalo's season-high 241 yards on the ground. Undrafted Jeff Tuel (18-of-39, 229 yards) started in place of the injured Thad Lewis (ribs) and tossed a 59-yard touchdown pass to fellow rookie Marquise Goodwin for the Bills (3-6).

With the score tied at 13-13, Tuel connected with T.J. Graham across the middle before cornerback Marcus Cooper stripped the wideout of the ball. Hali alertly picked it up and rumbled in for the score.

Buffalo was threatening to add to its 10-3 lead early in the third quarter before Tuel and receiver Stevie Johnson crossed signals near the end zone. Tuel's throw landed in the arms of Smith, who raced down the sideline to tie the game with Kansas City's fourth interception return for a touchdown this season.

GAME NOTEBOOK: Kansas City trailed 10-3 at halftime, marking just the second time this season it entered the break on the losing side of the score. The Chiefs trailed Dallas in Week 2 and went on to win. ... After the Chiefs went three-and-out on their first possession, PR Leodis McKelvin scampered 89 yards on the ensuing punt to give the Bills an apparent early lead, but an illegal block in the back by LB Nigel Bradham nullified the play. ... Kansas City won its first nine games in 2003 and finished with 13 victories before falling to Indianapolis in the divisional round of the playoffs.