Manchester United beat Liverpool 3-0 at Old Trafford to extend their lead at the top of the Premier League and put the head on their rivals, Arsenal and Chelsea, who meet at Stamford Bridge this afternoon.

The result puts United six points ahead of Arsene Wenger's side in second place, though Arsenal can cut the gap back to three points by winning today against their West London rivals, who are in third.

United were deserved winners, although Rafael Benitez's side might feel they were served an injustice when Javier Mascherano, the Liverpool midfielder, received a contentious red card in the first half.

Wes Brown scored the opening goal in the 34th minute when he beat Jose Reina, the Liverpool goalkeeper, to a Wayne Rooney cross and headed into the net.

Liverpool were reduced to ten men just before half-time when Mascherano complained about a series of strong tackles on Fernando Torres, his team-mate, and received a second yellow card from Steve Bennett, the referee.

Cristiano Ronaldo doubled United's lead with his 34th goal of a remarkable season in the 79th minute. Once again Reina was beaten to a cross, this time from a Nani corner, and the Portuguese winger headed home his first goal against Liverpool.

Nani put the game beyond Liverpool two minutes later when he collected a neat one-two with Wayne Rooney, skipped past his marker and finished excellently from the edge of the penalty area.

Ferguson was delighted with his side's performance. "It was a really good performance, a performance of maturity," he said. "We've seen a team mature over the last six months and today they hit their peak."

Asked to comment on the Mascherano's dismissal, he said: "He has been booked and kept badgering the referee. We've talked about dissent and I think that was dissent."

The United manager added that there is still much life left in the title race. "It's going to go right to the end, Chelsea and Arsenal going really well," he said. "We've beaten a strong Liverpool side playing good football."

Rooney was similarly enthused by a victory over one of United's bitterest rivals. "It's always nice to beat Liverpool and it's opened up a bit of a gap now at the top of the league," he said. "I'm delighted with the win."

Asked whether he thought the red card was a turning point, Rooney said: "We were always on top. The Liverpool players were tired at the end, but overall I don't think it would have made any difference.

"We know it's in our hands now. We have to try and win as many games as possible and stay top of the league. We've got a good mix in the dressing room and we know what we have to do between now and the end of the season."