Sir Alex Ferguson is predicting "absolute chaos" on FA Cup semi-final weekend.
With both matches at Wembley and all four teams heading down from the north west, travel routes are going to be congested on a weekend that also includes Arsenal's high-profile Premier League encounter with Liverpool, plus the London Marathon.
Ferguson has never viewed Wembley as an ideal venue for the FA Cup semi-finals anyway.
But this season, he feels it makes even less sense.
"There will be 60,000 people coming down from Manchester - think about how much petrol is used for that?" he said.
"Think of the amount of people from the north west driving down there.
"Stoke fans, Bolton fans, City fans, United fans - and on the same weekend Liverpool fans are travelling down. And you've also got people coming down to see the London Marathon.
"It's going to be absolute chaos.
"I don't think the cost of people travelling down to Wembley is considered.
"You've got Villa Park and Anfield just there on your doorstep.
"It's quite incredible but there's nothing that can be done about it."
Semi-finals have been played at Wembley since 2008 and are also part of the business plan on which the new stadium was constructed.
Although Ferguson comes from the traditionalists' camp, the FA argue Wembley's 90,000 capacity allows far more spectators to watch the two games, which in this instance is particularly pertinent.
Neither Stoke nor Bolton have played in a semi-final for some considerable time, so both are likely to have massive followings for their meeting on April 17.
One day earlier, City take on United in the FA Cup's first post-war Manchester derby semi-final, ensuring capacity will be reached easily.
Not that Ferguson expected it to be any other way once he knew which four teams would remain in the competition.
"It's the draw everybody thought would happen," he said.
"I had a strong feeling that we'd get City.
"I'm not saying there's a hot ball and a cold ball, but it's maybe the kind of draw that a lot of people wanted - and maybe a lot of people didn't want."
Before that, United have two crucial Premier League games to play, starting at West Ham on Saturday, before they entertain Fulham at Old Trafford on April 9.
If the Red Devils can win those two matches, they will retain a current five-point advantage over Arsenal, although with Chelsea closing fast, Ferguson accepts nothing can be taken for granted.
"It looks as if its going to be us and Arsenal, but you never know," he said.
"Manchester City, Chelsea and Tottenham are still in the frame. You can't dismiss them. But there are some important games coming up.
"The way I look at it is every game is a winner now.
"These are must-win games, in the sense that every time you get three points, it's another step closer to the finish line."