United breeze past Saints

But Sir Alex Ferguson's side were more than aided by the benevolence of referee Mike Riley who sent off Southampton's Matt Paterson for violent conduct in the first half and then incorrectly awarded United a second-half penalty.

Goals from Danny Welbeck, Nani and substitute Darron Gibson earned United a simple passage into the next round.

United's first opening arrived in the fifth minute courtesy of a fine through ball from Dimitar Berbatov. The Bulgarian striker cleverly sent Ryan Giggs racing into the penalty area but the United winger's effort was far too high to trouble Kelvin Davis in the Southampton goal.

In the 16th minute, Nani forced Davis into a fine save before Anderson had an effort tipped over the crossbar.

But the goal United had been threatening finally arrived in the 19th minute through Welbeck. Nani's corner was headed against the crossbar by John O'Shea and Welbeck had the simple task of nodding home the rebound from point blank range.

Southampton's plight worsened in the 35th minute when Paterson was sent off. The Southampton player, who had already been warned about a number of heavy challenges, was dismissed for violent conduct after a lunge on United defender Nemanja Vidic.

Southampton's cause was well and truly lost just after the break when Riley awarded United a penalty for handball against David McGoldrick.

Oliver Lancashire brought down Welbeck on the edge of the penalty area and when Nani tried to get the ball over the defensive wall, Riley adjudged that McGoldrick had blocked its path with his arm. Nani took full advantage though when he converted the spot-kick - sending Davis the wrong way.

United dominated the closing stages and were rewarded with a third goal in the 81st minute when Gibson smashed home a cross from Wayne Rooney.