Cape Town - Manchester United manager Ole Gunnar Solskjaer has warned his players to expect an aggressive Manchester City side to be 'snapping at their heels' and fouling them in Wednesday's derby.
The two sides will meet in a high-stakes clash at Old Trafford, with City locked in a tight Premier League title race with Liverpool and United scrapping to get into the top four.
City have previously been accused of 'tactical fouling' to prevent counter-attacks when they are pressing high up the pitch, and Solskjaer expects to see that on Wednesday.
"We have got to be ready for the press and the quality they have got on the ball," he said.
"When we win it, we have got to be ready for their aggression because they will snap at your ankles and heels and kick you.
"They will not allow us easy counter-attacking. There will be fouls, no doubt about it."
For the time being, their 4-0 loss to Everton was United's sixth defeat in their last eight matches as goals from Richarlison, Gylfi Sigurdsson, Lucas Digne and Theo Walcott handed the Toffees a convincing and deserved win.
Asked whether his players were hurting after a heavy loss, which keeps them sixth in the Premier League, Solskjaer responded: "I don't know. 'You have got to ask them. I have asked them, you're not going to get the answer from me."
However, he has demanded an improvement in their effort levels, harking back to his own playing days under Sir Alex Ferguson, the Norwegian added: "If you want to play at this club, it has to mean more. I want my team to be the hardest working team in the league, that is what we were under Sir Alex, that's what we've always been.
"No matter how much talent you have got, you run more than anyone. We know our fitness is nowhere near good enough. But we have to stick together as a team.
"You can't change your whole squad. One step at a time. I am going to be successful here and there are players who won't be part of that successful team but many of these do have it."