"We certainly need to get better offensively,Discount NFL Jerseys," coach Jason Garrett said. "We did a good job of running the football at different times. But, we weren't able to sustain drives."
Add Kellen Moore to the Cowboys growing list of quarterbacks unable to provide a spark.
The Cowboys dropped to 1-10 in games without Romo, who's sidelined by a broken collarbone.
Another miscue then sealed the loss for Dallas,China Jerseys Cheap.
The Bills had used more than 4 minutes when Gillislee scored. Facing second-and-5 at midfield, Gillislee took a handoff to the right and got key blocks from guard Richie Incognito and receiver Chris Hogan.
Butler led the team with four catches for 74 yards. Darren McFadden had 99 yards rushing.
Garrett liked what he saw from Moore, but said he hasn't yet determined who will start next week.
"I thought he operated well and made some big plays in the game, but obviously not enough for us offensively," Garrett said. "We need to score more points."
In the third quarter, Moore led the Cowboys to the Buffalo 26 only to have his low pass tip off Butler's fingers and into the hands of linebacker A.J. Tarpley.
Safety Barry Church, who forced a fumble, broke his right arm.
Moore went 13 of 31 for 186 yards passing and an interception, a week after Matt Cassel was benched during a 19-16 loss to the New York Jets.
Against Buffalo, they were limited to 307 yards of offense. They've combined to score just four touchdowns in their past five games. And Dallas has managed to score one or fewer touchdown eight times.
That time has all but run out for the Cowboys, who at 4-11 are eliminated from playoff contention in preparing to close their season hosting Washington next week.
Tight end Jason Witten was limited to just one catch for 12 yards. But that was still enough for Witten to extend his streak of games with a reception to 118, to set the franchise record ??” one more than Hall of Fame receiver Michael Irvin.
"We can make excuses and all that stuff," said Moore,Wholesale Jerseys NFL, referring to an offense that was also minus injured star receiver Dez Bryant. "Bottom line is, we had an opportunity to score points, we didn't. Hopefully,Wholesale Jerseys Store, we learn from this."
Buffalo snapped a two-game skid and won for just the second time in six games.
Lucky Whitehead was stripped of the ball by Tarpley and fumbled the kickoff following Gillislee's touchdown. That allowed Buffalo to run out the clock.

The Bills (7-8), who are also eliminated from contention,NFL Jerseys China, sealed the win on Mike Gillislee's 50-yard touchdown run with 2:25 remaining.
The Cowboys settled for Bailey's 22-yard field goal after Moore overthrew Brice Butler in the end zone on third-and-goal from the 4 in the second quarter.
In making his first career start, Moore failed to produce one touchdown drive as Dallas settled for kicker Dan Bailey hitting two of three field-goal attempts in a 16-6 loss at the Buffalo Bills on Sunday.
ORCHARD PARK, N.Y. (AP) ??” The Dallas Cowboys offense is still going nowhere without Tony Romo.