The Minnesota Vikings failed with a two-point conversion attempt with 25seconds left as the Dallas Cowboys hung on for their 11th straight NFL win.
Dallas escaped with a 17-15 road victory after Sam Bradford's throw sailed over the end zone, though the Vikings quarterback was caught with a clear hand to the helmet from Cedric Thornton which was not called. A false start had pushed Minnesota five yards back before the conversion attempt.
Bradford had picked out Jerick McKinnon with a three-yard touchdown pass to set up the opportunity to tie the game.
The Vikings had kept themselves in the game with a fierce defensive effort, holding the Cowboys to season lows in points as well as yards (264) and first downs (13), while also forcing two turnovers.
But it was a Vikings turnover - Adam Thielen's fourth-quarter fumble - which set up a Dez Bryant touchdown and gave Dallas all the breathing space they would need.
Bryant had earlier hauled in a 56-yard catch to set up the opening Dallas touchdown - a one-yard run from Ezekiel Elliott.
Vikings special teams co-ordinator Mike Priefer was in charge of the team with coach Mike Zimmer absent due to emergency eye surgery.
While the 11-1 Cowboys stand on the brink of a playoff berth, the Vikings have lost six of their past seven to sit at 6-6.