City, who are battling for the Premier League title with Liverpool, will be looking to get maximum points at Old Trafford but Guardiola expects a tough test despite their 4-0 thumping away to Everton on Sunday.
“I expect the best United is going to [turn up] tomorrow. They have pride. Football players always have pride to do their best and tomorrow it is going to happen," he told Sky Sports.
“So we will prepare for the game like always with their strong points and their weak points and try to win the game.
“I am close to [Ole Gunnar] Solskjaer, I understand his position perfectly. We are alone, we feel alone, I understand his position because it happens to all the managers around the world.
“It is the reality, we have to accept it. If not, stay at home. I understand him perfectly and I am with him. I support him.”
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