A bitter defeat by Liverpool in the FA Cup at the weekend means United's only chance of silverware this season now is the Premier League, and Stoke defender Robert Huth admitted there may be better times to visit the reigning champions.
He told Press Association Sport: "It's not ideal they lost - they will probably turn up now and be on fire against us. That's what we have to expect.
"Whenever they seem to lose a game, in the next one they perform almost like the old United, so it will be a tough game.
"I think they will come out all guns blazing. It will obviously have been a frustrating result, losing against Liverpool.
"They're out of the FA Cup, out of the Champions League, so it's the league for them now, so I'm sure they'll be up for it."
Huth said Stoke would take heart from Blackburn's performance at Old Trafford last month when they Rovers stunned United with a 3-2 victory despite being bottom of the table at the time.
He added: "Blackburn showed it can be done. It's a 90-minute game. Anything can happen, we just have to be positive.
"Blackburn frustrated them. You could argue Man U were not at their best, but it's still a tough place to go and win.
"I'm sure we'll be looking at previous matches where teams have done well against them, so maybe we can get something."
Huth also believes that the Premier League trophy is more likely to end up with Manchester City than United.
"I think City are in the slightly better position at the moment," he said. "They've the slightly bigger squad with people who can come in and do a job."
Stoke boss Tony Pulis believes Ferguson will bring back the big guns such as Wayne Rooney to start the match on Tuesday.
Pulis said: "I looked at their [FA Cup] game a little before ours and there was no Rooney, Nani, Anderson, Carrick, Jones and everybody else, so it's going to be a tough game.
"We know how difficult that game will be. They've just got knocked out of the FA Cup, and I'm sure Sir Alex will be absolutely focused on winning the Premier League."
Matthew Etherington is a doubt for the trip to Manchester after suffering a groin injury in the weekend's FA Cup win over Derby.
Mamady Sidibe (knee) is a long-term absentee but apart from that Pulis has virtually a full squad to choose from.
The Stoke manager added that he is not chasing any last-minute transfers before the window closes - unless a good deal drops into his lap.