Sir Alex Ferguson has admitted the Chelsea revolution will not be easy for Manchester United to combat on Sunday (3.00am Monday AEDT) - even though he knows exactly what the Blues are going to do.
Since it last English Premier League title win in 2010, there has been a growing clamour for Chelsea to reinvigorate its squad.
Neither Carlo Ancelotti, nor
The catalyst was Didier Drogba's departure for
And, just as owner
"Chelsea always had that alternative route of playing with Drogba up front," said Ferguson.
"They could play it long or they could play it through midfield.
"Now it's straightforward. It's through midfield all the time.
"But it's not an easy system to deal with. Oscar and Hazard are similar type players. And with Mata as well they all play in behind the main striker.
"We just have to find a way of dealing with it."
Prior to Tuesday's Champions League defeat in Donetsk, the system had been an unqualified success.
Chelsea so far dropped just two points in the Premier League - a goalless draw at Queens Park Rangers - reached the last 16 of the Capital One Cup and steered itself into a handy position in the Champions League.
Ferguson might hope that trip to
For there will be none to come from a remarkable record at Stamford Bridge, where they have not lost in domestic combat to Sunday's opponent since 2002.
"It's an amazing record," said Ferguson.
"It will change - sometime. Hopefully on Sunday.
Despite that lack of success, it could hardly be claimed United's visits to the King's Road have been uneventful.
There was the post-match battle between
Two seasons ago, Ferguson was given a five-match touchline ban after a rant at the performance of referee
Last term, in a quite amazing game, United hauled itself back from three goals down only to need an astonishing save from
"In the main I don't think we've played badly," said Ferguson.
"We have actually played well in the games we have lost only to get bad decisions against us.
"Last season we did really well to rescue it after being 3-0 down and should have won it really."
"They could also have lost it though."
In that single save from Mata in stoppage time, De Gea proved why Ferguson was willing to spend £18 million signing him from Atletico Madrid and why, for all the doubts over his size and failure to command his box, United will persevere.
"His strength is shot-stopping," said Ferguson.
"At the moment you would say he's a goal-line goalkeeper, there have been plenty of those over the years.
"The area which we are looking at is his strength. He's getting stronger all the time and he is already very quick, so he is getting there."
United will be without midfielder
English Premier League
Aston Villa has completed the signing of striker Nicklas Helenius from Aalborg.