Although United are used to receiving negative reactions on their travels, Upton Park ranks alongside Anfield and Elland Road as a ground where the atmosphere is at its hottest.

It was a topic of conversation earlier this week when former Hammers boss Alan Pardew paid a visit to United's Carrington training base.

Pardew did not have an answer either, just an acknowledgement the crowd on Sunday will be at its most intense.

"I don't know why there is an extra intensity to the West Ham games," said Ferguson.

"Alan Pardew said it is the one game their fans really get revved up for, even more than Arsenal and Tottenham. It is unusual."

The relationship between the two clubs hardly improved when Paul Ince was pictured wearing a United shirt when he was still a West Ham player.

Ferguson feels it goes back much further, although Rio Ferdinand should be immune as he generally gets a warm ovation when he returns to his old club.

Wayne Rooney, Patrice Evra, Nani and Brazilian twins Rafael and Fabio all return to a United squad which has kept 12 successive clean sheets and has powered to the top, two points ahead of Liverpool heading into the weekend fixtures with a game in hand.

Little wonder United are favourites to register an 18th league title, which would equal Liverpool's proud record that has stood since the Merseysiders last won the title in 1990.

However, Ferguson is refusing to look beyond the present. And, despite the healthy look of the league table just now, the Red Devils boss is planning for a battle that goes right down to the wire.

"You have to put your mind to the possibility that the title could go down to the last few games," said Ferguson.

"I expect the worst and hope for the best."

Certainly Ferguson would happily head to Hull on the final day under the same circumstances as he travelled to Wigan last season knowing a win would seal the trophy.

"That would be fine," he said.

"It would be a position I would take at the start of the season and it could very well be that way this year."