Chelsea now the main title threat says Ferguson

He has eulogised over their collective strength all season but the events of last Sunday at Stamford Bridge have convinced Sir Alex Ferguson that Arsenal are no longer the side he most has to fear during the title run-in.

Arsenal's late defeat to Chelsea, allied to their tough three-match engagement with Liverpool, have persuaded him that Avram Grant's side are the one now most likely to overhaul United's five-point advantage. "The three games Arsenal have got against Liverpool will make a big difference," Ferguson said yesterday, as he contemplated the arrival of Aston Villa for a match which, with Chelsea playing on Sunday, could extend his side's lead to six points – even if Arsenal win at Bolton. "Chelsea have also got the easier draw [in Europe]."

Ferguson considers Arsène Wenger's midfield injuries to be another critical factor but he also reserved his wrath yesterday for the international friendlies which have deprived him for six weeks of Darren Fletcher – who sustained a knee ligament injury in the last minute of Scotland's 1-1 draw in a friendly with Croatia at Hampden Park.

"Darren should have played only 45 minutes, 60 minutes at most. But instead he was heading for a full game before he got injured," Ferguson said. "It is a bad blow losing Darren and again shows the futility of playing friendly games. It is crazy and supporters will stop going to these kind of games anyway, paying all that money and travelling. I think every manager knows, deep down, that they are a waste of time."

For Ferguson, the answer is to play friendlies when the season is finished – though the training camps which Walter Smith and Alex McLeish have tried with Scotland were also something he suggested to Terry Venables when he was England coach.

The 3-0 win over Liverpool last Sunday provided Ferguson with the luxury of looking ahead to a crucial four days which take his side to in-form Roma after the challenge of a Villa side in hot pursuit of a European place.

The push by Luciano Spalletti's side for a Scudetto – they are now only four points behind Internazionale – could play in Ferguson's favour as Spalletti might well play his strongest side against Cagliari this weekend. "Roma can win the league, they are only a few points behind and have an absolutely fantastic chance which might well help us too," he said.

At Old Trafford today there may be several changes from the side which beat Liverpool, though the rest of United's international contingent reported back fit and Nani and Cristiano Ronaldo are expected to be available to play after missing Portugal's midweek friendly.

Ferguson wants his team to maintain the standards they showed in beating Liverpool, pointing to the return to form of Paul Scholes as potentially key to their title hopes. "We have to use that as a barometer for the rest of the season. Last Sunday was a great sign for me in terms of the confidence of the team and the composure they showed in their game, which I thought was top class," said Ferguson.

"Most rewarding for me was the form of Paul Scholes. After three-and-a-half months out he was taking his time to get back to the real Paul Scholes' form but last Sunday he was head and shoulders above every player on the pitch and absolutely magnificent. That gives us great confidence."

Striker Louis Saha is again absent for United with a hamstring injury that will keep him out for up to three weeks.