A loss to Roberto Di Matteo’s early pacesetters at Stamford Bridge would open up a seven-point gap between the Blues and Ferguson’s men – and the United boss is wary of the threat posed by the west Londoners, who have only dropped two points so far this term.
“We don’t want the gap to open, this could be a league in which you will suffer if you lose the big ones,” said Ferguson.
“We could not afford to lose to Tottenham the way we did – 2-0 down and then 3-1 down. You cannot do that at this level.
“If we get any more of that, we will be in trouble. Chelsea are undefeated in the Premier League and that gives you an idea of the level of consistency they have produced.”
Robin van Persie has hit the ground running at Old Trafford since his £24m move from Arsenal during the summer, netting eight goals in 10 games for the Red Devils.
And Ferguson was full of praise for the Dutchman, who scored a hat-trick for Arsenal at Stamford Bridge last season, ahead of Sunday’s clash.
“His performances are getting better all the time,” Ferguson said. “Against Stoke last week and on Tuesday night against Braga his movement was fantastic.
“We bought him for that reason – to make a difference, to give us maturity up front and some flexibility. With [Danny] Welbeck, [Javier] Hernández, [Wayne] Rooney and Van Persie, we have some fantastic alternatives and that could make the difference.”
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