Bulls' coach Steve McNamara hailed the best fightback he has been involved in as Super League's last unbeaten record ended in stunning circumstances. Matt Orford was the star with two tries and a big part in another as Bradford overturned a 20-point deficit that made them look a hopeless case at the break.
McNamara told them some home truths at half-time and a transformed display saw them snatch the spoils with Glenn Hall's 79th-minute dive over the line and Orford's third goal.
"I'm very pleased with the second-half performance, but we can't keep doing that every week," he said. "It's too hard and it will catch up with us eventually."
The qualities that have taken Wigan to the top of the table were there for all to see in the first half at Odsal. Michael Maguire decided against recalling Cameron Phelps, instead leaving Roberts at full-back and being richly vindicated by the first two tries. Roberts set up Darrell Goulding for the first after two minutes before setting off on an 80-metre run, which saw Harrison Hansen dive over.
Roberts and Sean O'Loughlin paved the way for Sam Tomkins, while Pat Richards scored his eighth try of the season with almost laughable ease, his two goals taking the damage at the interval to 20 points.
The transformation after the break was startling. After 46 minutes, a move begun by Matt Orford and finished by Brett Kearney gave them their first points – the first conceded by Wigan in over two hours of rugby.
Three minutes later, the former Wigan hooker, Wayne Godwin, threw the pass from dummy-half, Orford stepped back against the sliding defence and, with the addition of a second conversion, the Bulls were somehow back in the match.
The precision had gone out of Wigan and they were punished seven minutes from time when Orford got over. This time, however, he missed the kick that would have applied the extra pressure. That hardly mattered when, two minutes from time, Hall crashed over by the posts, leaving Orford the easiest of kicks for a famous if unlikely victory.
Bradford: Halley; Crookes, Sykes, Nero, Reardon; Kearney, Orford; Scruton, L'Estrange, Lynch, Langley, Whitehead, Menzies. Substitutes used: Godwin, Worrincy, Kopczak, Hall.
Wigan: Roberts; Goulding, Gleeson, Carmont, Richards; S Tomkins, Leuluai; Fielden, Riddell, Coley, Hansen, J Tomkins, O'Loughlin. Substitutes used: Bailey, Deacon, O'Carroll, Paleaaesina.
Referee: P Bentham (Warrington).