LEEDS 1 (Tonge 80 pen), WATFORD 6 (Vydra 27, 82, Abdi 62, Yeates 74, Murray 90+4, Deeney 90+8)
Leeds: Kenny, Byram, Green (Lees 45), Peltier, Pearce, White (Hall 46), Norris, Austin, Tonge, Diouf (Brown 46), Varney. Subs: Ashdown, Kisnorbo, Becchio, Dawson.
Watford: Almunia, Yeates, Doyley, Vydra, Anya, Abdi (Hogg 68), Cassetti, Smith, Hoban, Geijo, Ekstrand. Subs: Murray, Thompson, Bond, Chalobah, Forestieri.
Referee: T Kettle
Sent-off: Pearce (Leeds)
United manager Neil Warnock made a number of changes to his starting line-up for the visit of Watford. Teenager Chris Dawson was also named among the substitutes for the first time.
The changes saw Paul Green playing in a deeper defensive role with Sam Byram and Aidy White operating in wing back roles.
United fashioned out the first chance of the game after good work by Rodolph Austin and Byram created an opening for David Norris, but his strike was deflected to safety. Watford also had to scramble the ball clear after Jason Pearce headed a El-Hadji Diouf free-kick back into the box.
The visitors went close themselves on 20 minutes, but as United moved foward, Diouf fed Luke Varney and Manuel Almunia had to react well to deny the Leeds marksman.
But the visitors were in front on 27 minutes when Matej Vydra capitalised on a quick break forward and, while United looked in vain for an offside flag, the Watford man smashed it past an advancing Kenny.
And there was worse to come for Leeds right on the stroke of half-time when Pearce was given a straight red card following a challenge on Vydra. United also re-shuffled with Tom Lees coming on for Green before the break.
There were two more changes at the break, Ryan Hall replacing El-Hadji Diouf in the front-line and Michael Brown coming on for Aidy White.
But the second half didn't start any better for Leeds after Austin went down in pain, clutching his ankle, and received immediate treatment before being stretchered from the field. Austin's departure reduced Leeds to nine men for the remaining 40 plus minutes of the game.
And it was 2-0 to Watford by the hour-mark when Almen Abdi tucked the ball home from distance after Watford were able to explot the added space.
Moments later, it was Watford's Abdi who appeared to suffer a freak injury, and he was stretchered off clutching his shoulder.
But Watford still found a third goal when Mark Yeates curled a free-kick beyond the reach of Kenny.
Watford goalkeeper Almunia was called into action 13 minutes from time when he ahd to get down well to save a Hall free-kick, but as the game headed towards its inevitable conclusion, the visitors were in a secure position.
United did restore some credibility when Luke Varney was brought down in the box and Michael Tonge stepped up to convert the penalty.
Watford soon restored their three-goal advantage, though, when Vydra again profited from another quick break before lifting the ball past Kenny.
Ten minutes were added on to the 90 for a game that had been disrupted by two serious injuries, and Watford added a fifth goal during that period when Sean Murray tucked the ball in the far corner after another break.
The visitors made it six in the eighth minute of stoppage time when Troy Deeny tucked the ball home from just inside the area.