Vitesse coach Theo Bos had promised his team would do their best to play the role of party poopers at the DSB Stadion as Louis van Gaal's team looked to be crowned champions on home turf.

All had seemed to be going to plan for AZ when fit-again striker Mounir El Hamdaoui opened the scoring in the 19th minute.

But Ricky van Wolfswinkel restored parity for the visitors nine minutes from time and then substitute Alexander Buttner struck an 83rd-minute winner to silence the home crowd.

Second-placed FC Twente also lost - 1-0 at Feyenoord courtesy of Roy Makaay's 78th-minute penalty - meaning a point would have been enough for AZ to win the league tonight.

The match at De Kuip was an ill-tempered one which finished 10 versus 11, Giovanni van Bronckhorst sent off on the stroke of full-time for the hosts after Douglas and Cheik Tiote had seen red for Steve McClaren's side.

AZ are still in an enviable position despite their defeat, however. They can only mathematically be caught by third-placed Ajax, who are 12 points behind and play the first of their four remaining games at PSV Eindhoven tomorrow afternoon.

Elsewhere tonight, NEC Nijmegen's pursuit of a Europa League place took a blow as they were held to a 1-1 home draw by struggling Roda JC.

And it might have been worse for NEC boss Mario Been as his side needed a Bas Sibum equaliser nine minutes from time after Sekou Cisse had put the visitors from Kerkrade ahead.

De Graafschap, meanwhile, slumped closer to relegation as Marcus Berg's penalty condemned them to a 1-0 loss at home to FC Groningen.