Spiller scored twice and finished with 123 yards rushing in a 35-17 win in Buffalo's home opener. Spiller, who also had 47 yards receiving, picked up where he left off last week, when he took over for injured starter Fred Jackson and enjoyed a career-best 169 yards rushing in a 48-28 loss against the New York Jets.
The Bills' high-priced Mario Williams-led defense then did the rest Sunday. Kyle Williams had two of the team's five sacks, and Buffalo forced three turnovers.
That included linebacker Nick Barnett forcing Peyton Hillis' fumble at the goal line to snuff out a scoring drive late in the first half. Mario Williams also recovered quarterback Matt Cassel's fumble, which led to Scott Chandler's 10-yard touchdown catch in a first half during which the Bills took control by building a 21-0 lead.
Fitzpatrick shrugged off last week's three-interception outing by going 10 of 19 for 178 yards and two touchdowns, including a 49-yarder to Stevie Johnson. And Buffalo's special teams contributed: Leodis McKelvin returned a punt 88 yards to make it 35-3 with 3:46 left in the third quarter.
It was a complete reversal for the Bills who against the Jets turned the ball over four times, failed to get any pressure on Mark Sanchez and allowed Jeremy Kerley to return a punt 68 yards for a score.
For Kansas City, it was the same-old sloppiness by a team coming off last week's 40-24 loss to Atlanta.
Kansas City opened a season 0-2 for the sixth time in seven years. That includes last season, which they opened with a 41-7 home loss to Buffalo.
Cassel finished 23 of 42 for 301 yards with two touchdowns and an interception, with much of that production coming after the Bills had built a 35-3 lead. Dwayne Bowe scored both touchdowns on 33- and 2-yard catches in the final seven minutes.
The Chiefs' running attack sputtered. Hillis had 66 yards rushing, and Jamaal Charles just 3 yards on six carries.
Kansas City managed just four first downs and 71 yards on its first five possessions. The Chiefs then came up empty on their sixth possession, and after Cassel marched them 77 yards on eight plays. Facing second-and-goal at the 1, Hillis took the handoff, but was tripped up immediately by Barnett and then lost control of the ball as he fell forward.
Safety Bryan Scott jumped over a pile of players to get control of the ball before Hillis could recover.
The Chiefs were so thoroughly outplayed on both sides of the ball in the first half that Spiller's 139 yards from scrimmage nearly matched Kansas City's 148 yards net offense.
The Chiefs defense struggled despite welcoming back two regulars. Star pass-rushing linebacker Tamba Hali returned after serving an NFL-imposed one-game suspension for violating the league's substance abuse policy, and cornerback Brandon Flowers returned after missing the opener with a foot injury.
With Jackson expected to miss another three weeks with a sprained right knee, Spiller was unstoppable in scoring on the Bills' second and third possessions.
He accounted for 48 of Buffalo's 84 yards in scoring on a 17-yard run 13 minutes in. Spiller then scored on a 3-yard run on the Bills next drive, which he helped set up with a solid 38-yard run, when he burst through the middle before being tackled at the Chiefs 12.
Spiller became the fourth Bills player to reach 100 yards in the first two games of a season, joining Fred Jackson, Thurman Thomas and O.J. Simpson, who did that twice.
Kansas City did lose tight end Kevin Boss to a head injury in the second quarter. After making a catch over the middle, Boss stumbled backward and hit the back of his head on the turf at the same time safety Da'Norris Searcy struck him on the side of the helmet with his forearm.
Boss appeared woozy as he walked off to the sideline. Searcy was penalized for a blow to the head.
McKelvin's TD return was the second of his career, and the second-longest in team history, 3 yards short of the record set by Keith Moody in 1977.
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