Deco thinks Chelsea have too much quality in attack for Manchester United to contend with.

The Premier League's top two meet on Sunday, and Deco is backing the Blues - currently top by two points - to extend their lead.

The Portuguese midfielder is going into the game fully confident that Didier Drogba will fire them to victory.

"The big difference between us and United is in attack," said Deco.

"Drogba is enjoying a spectacular moment in his career and is superior to the front-line of United.

"For me, Didi will be the key - the star of the match, for sure."

Deco also believes that the game is worth more than just three points.

"This match has a four-point value, an extra one for the blow to United's morale because they also failed to beat Liverpool," he said.

"If they fail in London they will need to think very much about things in the following days.

"Victories in classic matches like this always have enormous value.

"For Chelsea to begin November with a five-point advantage over United will be sensational."

Deco also says that he has never been happier in England following his move from Barcelona in 2007.

"I'm enjoying my best form since arriving from Barcelona. Physically I'm perfect."