Dan Reynolds reporting

Alan Smith was both hero and villain as his strike boosted Leeds' Champions League ambitions before the fiery striker was shown the red card.

The England Under-21 ace's 13th goal of the season in the first half ensured David O'Leary's side became only the second side to claim a Premiership win at the Stadium of Light this campaign.

But Smith soon turned from saint to sinner when he received a second yellow card 19 minutes from time for a foul on Sunderland's French defender Patrice Carteron.

Australian ace Mark Viduka wrapped up the points that take Leeds above Sunderland in third place in the Premiership when he converted former Inter Milan star Robbie Keane's injury time cross.

It was Viduka's 20th goal of the season and his fifth strike in successive matches to stretch Leeds' unbeaten Premiership run to nine matches.

But it could all have been so different for Peter Reid's men who wasted a host of guilt-edged opportunities, most notably when Argentine star Julio Arca blazed over the bar with Leeds keeper Nigel Martyn stranded.

Both teams started at a furious pace and Sunderland went close to opening the scoring on six minutes when Arca set up Gavin McCann inside the box, but Rio Ferdinand got across to make a solid block.

David O'Leary's side were rocked minutes later when Olivier Dacourt was stretchered off following a collision with Don Hutchison and the visitors looked to be missing his presence as Stefan Schwarz sent a volley inches wide and substitute Eirik Bakke had to make a desperate goalmouth clearance.
 
Peter Reid's men continued to dominate and forced a series of corners before the game erupted into controversy when Kevin Phillips raced onto a superb through ball from Carteron before being poleaxed by Ferdinand just as he was set to pull the trigger.

Referee Steve Dunn refused to award the home side a penalty for the incident and the Sunderland top-scorer's misery was compounded when Australian ace Harry Kewell headed Harte's deep corner back across goal for Smith to power past Thomas Sorensen.

The Black Cats almost equalised on 44 minutes when defender Emerson Thome's header was cleared off the line by David Batty before referee Dunn was again at the centre of controversy two minutes after the break when he failed to penalise Jody Craddock after the Sunderland defender sent Smith tumbling.

Leeds almost doubled their lead in the 56th-minute when Sorensen pulled off a spectacular save from Kewell before the visitors were reduced to 10 men when Smith was harshly shown a second yellow card for lashing out at Carteron, who appeared to make a meal of the incident.

The Black Cats tried desperately to make their numerical advantage pay and Leeds keeper Martyn pulled off a breathtaking save to deny Arca a brilliant equaliser on 72 minutes, before Danny Mills twice got in desperate blocks to keep out McCann.

Schwarz sent a dipping 20-yard volley just over the bar 12 minutes from time but Arca wasted a golden opportunity to level it on 82 minutes after Martyn dropped McCann's cross, but the South American side-footed his shot over the empty net.

That miss proved even more costly in injury time when substitute Keane crossed for former Celtic star Viduka who finished coolly to wrap up the points.

MAN OF THE MATCH: Rio Ferdinand (Leeds)
The £18 million man kept Sunderland hot-shot Kevin Phillips at bay and was brilliant throughout Leeds' victory.

Sunderland: Sorensen, Carteron, Craddock (Varga 75), Thome, Gray, McCann, Kilbane (Butler 67), Schwarz, Arca, Phillips, Hutchison (Dichio 66).
Subs Not Used: Williams, Macho.
Booked: Varga.

Leeds: Martyn, Harte, Radebe (Kelly 45), Ferdinand, Mills, Kewell (Keane 83), Batty, Dacourt (Bakke 9), Bowyer, Viduka, Smith.
Subs Not Used: Robinson, Wilcox.
Sent Off: Smith (71).
Booked: Radebe, Smith.

Att: 48,285
Ref: S Dunn (Bristol).