Sir Alex Ferguson refused to write off Arsenal's title chances despite seeing United move four points clear of Arsene Wenger's men. United's 4-0 win at Bolton saw them take advantage of the Gunners' 1-1 draw at Birmingham earlier in the day, while they once again moved a point ahead of Chelsea, who had temporarily gone to the top of the table with a 7-1 win against Aston Villa. But Fergie insists it remains a three-horse race. He said: I think with the league the way it is, every result is going to be important. Today was emphatic in terms of keeping ahead of Chelsea. It was a bad one for Arsenal to drop points so late on against Birmingham and they are now four points behind us. But we will all drop points the name of the game is the drop the least. Two goals from Dimitar Berbatov inspired United to victory at the Reebok, while an own goal from Jlloyd Samuel and a late strike from substitute, Darron Gibson was a resounding response to the marker put down by Chelsea earlier in the day. While Ferguson highlighted the outstanding displays of Berbatov and Nani in particular he credited Edwin van der Sar for the victory after the Dutchman's outstanding save to deny Fabrice Muamba when United led 1-0 before half time. It was a magnificent save, said the United boss. It was a match-winning save. Going on to praise Berbatov, who played as a lone striker in place of Wayne Rooney, he added: He can play there, but his preferred position for us is behind the strikers. He proved he can play there and he had Ryan Giggs close to him all the time. He was always a threat. Of Nani's continued impressive form, he added: He's been playing like that for weeks. He made two goals. He's signed a new contract, he's young but he is maturing and that's what we want to see.