Cape Town - Manchester United manager Ole Gunnar Solskjaer believes his charges need to step up their game when they meet Manchester City in the Carabao Cup semi-finals.
Having edged past Rochdale and shocked Chelsea, the Red Devils overcame League Two side Colchester, the lowest-ranked side left in the competition, on Wednesday evening.
The Essex side made the quarter-final harder than the 3-0 scoreline suggested, with Marcus Rashford and Anthony Martial scoring either side of Ryan Jackson's own goal in a one-sided second half.
United's reward is a January double-header against Pep Guardiola's City - a side Solskjaer's men secured a superb 2-1 win at on December 7.
"Fantastic days in Manchester," the 1999 treble hero said with a smile, reflecting on the semi-final draw.
"Of course, we do really respect them and, as I said after the game at the derby last time, it's, in my opinion, the best team in England.
"They can out football you, so we need to get our game heads on and be ready for them again.
"But we've shown them that we can cause them problems, so I think they'll be two fantastic games."
Rashford and Martial scored in a thrilling first half at the Etihad Stadium earlier in December, when United's counter-attacking prowess was key.
"We've looked at that game and, yeah, we're very pleased with the result and parts of that game," Solskjaer said.
"There are things we need to do so much better. The first 10 minutes, I was like you close your eyes and you think 'we've just got to hang in there'.
"We've got to stamp our authority more on them. There's not many that can do but we have to aim for that, and we have to strive for that.
"I don't think you'll beat City twice in a row or three times with the same tactics.
"So, we'll have to try to do something better than we did last time I think because I am sure Pep will definitely have his team fired up."