Manchester United boss Sir Alex Ferguson rates Jose Mourinho's Chelsea ahead of the current team. Roberto Di Matteo's side have set an ominous pace at the top of the league but Ferguson contends they cannot match the "ruthlessness" of the Mourinho-led Chelsea that won the title in 2005 and 2006, forcing the Scot to raise his own game at Old Trafford.

Ferguson declared: "I wouldn't say this is the strongest Chelsea team. I think if you go back to Mourinho's, they were ­formidable, and really difficult to play against.

"That period of Didier Drogba, a younger John Terry and Frank Lampard, who one year got 30 goals from midfield - they'll never get that again. They were a really powerful team, hard to beat - and ruthless."