The Red Devils have been without their £75 million striker for two games now, with a niggling knock seeing him drop out of the side for meetings with Bournemouth and Juventus.
Jose Mourinho’s men have collected 2-1 victories from each of those outings – both away from home – with Alexis Sanchez chosen to lead the line after being moved inside from the flanks.
Ince believes United have been forced to play “a different way” without the option to go long and feels that approach will serve them better when pitched into action against reigning champions City at the Etihad Stadium on Sunday.
The former Red Devils midfielder told Paddy Power: “Even if Lukaku is fit, Mourinho would be mad to play him in the derby.
“There are questions around whether Romelu Lukaku will be fit, but even if he is, Mourinho would be absolutely mad to play him.
“The results are plain to see.
“Alexis Sanchez was much improved against Juventus on Wednesday and it’s no coincidence that there was no Lukaku present.
“And, in general, when he hasn’t played, United look like a much better team.”
Mourinho has conceded that Lukaku, who is without a goal in his last nine appearances, is struggling for confidence at present, with Ince adding: “Without him, rather than booting in a long ball and hoping for the best, the United players are forced to play down the sides and get men in behind.
“No Lukaku has forced United to play a different way. And I’d go as far as to say it’s exciting to watch, they’re playing proper football again! They’re playing what I would call the United way.
“You can’t deny his goal scoring record, but there are certain balls which the midfield have been attempting now he’s not in the team, and there’s no way they’d have done that with him there.
“Sanchez, [Jesse] Lingard, [Anthony] Martial and even [Marcus] Rashford are all looking for those types of balls.
“It’s those kinds of players which will cause Manchester City trouble on Sunday, not Lukaku.”
United will make the short trip across Manchester this weekend sat seventh in the Premier League standings, nine points adrift of table-topping City.