After the Leeds match, when a 4-1 half time score was pulled back to 4-3 after the break to ensure a thrilling finale, fans are wondering which sort of performance it will be against Fergie's side.
And Tony insists there is a chink in their armour.
"They are not what they were and the best way to play them is the same way as we did against Arsenal," he says.
"We showed that day what a good side we can be, when we press the opposition, come out of the blocks really quick, hit the ground running and all the old cliches!
"In the last few home games it has been a really lethargic start, and it hasn't been until the second half that the lads have really got going - it must drive Glenn and Sarge absolutely bonkers after all the winding up that goes on.
"As soon as you cross the white line you have got to start the game quickly - if you don't against them, you are in trouble.
"The real West Ham is the one that faced Arsenal and Chelsea when we played quality opposition.
"We deserved to beat the best team in Europe, Arsenal, and we got a great win against Chelsea, so that is the sort of performance I am looking for - playing as a unit, pressing, and doing something positive going the other way.
"If you can't lift it for Man U you can't lift it for anyone, so I think we have got a really good chance."