Former Manchester United captain Rio Ferdinand says everything at the club is now "totally different" and urged supporters to accept the change in approach under Louis van Gaal.
United sit second in the Premier League table after Saturday's 3-1 win over Liverpool, but they have struggled to find any rhythm in their play.
Stories also emerged during the week, confirmed by Van Gaal, that skipper Wayne Rooney and Michael Carrick had approached the manager earlier in the season with concerns over squad morale.
Ferdinand says the days of Sir Alex Ferguson and Sir Matt Busby are long gone, and believes the fans will still be perfectly happy if trophies are won with Van Gaal's more possession-based football.
"The philosophy is completely different," the former England defender, who believes Man City have the best chance of success in the Premier League, said.
"Manchester United supporters now have to go away and re-educate themselves on how to watch Manchester United. Don't go there expecting to see free-flowing, attacking, gung-ho football.
"It's methodical, side to side, wait for an opportunity to come. It's a different type of football, very methodical, clear-cut pattern of the way he wants the team to play and it's totally different.
"I'm not saying that is the wrong way -- it is the way he chooses to play and it is not the way Manchester United are used to playing.
"If it brings success, Manchester United fans will be delighted, I will be delighted. It is just a different way of playing football.
"People who are old enough to remember those times [Busby, etc], they want fairytale and they're going to reminisce about old times and want to see what they're used to. The younger generation, they're not so attached to that and they can move on, but they're going to want to move on to a style that they like."
Ferdinand also revealed he and former defensive partner Nemanja Vidic had discussed the recent transfer business at United -- with Van Gaal having spent over a quarter of a billion pounds on new recruits -- and also questioned why a new centre-back was not signed over the summer.
"I just think, with Daley Blind playing centre-half every week, you think you've spent all that money, where is the centre-half?" he added.
"Because you didn't buy Blind as a centre-half. I was talking to Nemanja Vidic the other day on the phone and we were both saying the change is unreal in terms of the personnel and the transfer policy.
"We were saying, 'If they'd spent £50 million when we were there, we'd have won how much more?' If you'd got somebody at that time who was worth that. But the landscape changes. We were just reminiscing about old times and imagining if we'd had that amount of money to be spent on our squad.
"It is totally different and it doesn't look like anything that I knew when I was there. It's just all changed. Even the sponsor that's been there how many years, Nike, and now it's Adidas. Everything's changing, other than the groundsman and the chef."