Ole Gunnar Solskjaer knows Manchester United need to improve on their recent derby win if they are to triumph against 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 team 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 7 December.

‘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’s 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.’

City will certainly present a tougher test than Colchester, although their dogged defending and discipline frustrated the hosts in a goalless opening period at Old Trafford.

‘I thought we played well first half, but we were wasteful,’ Solskjaer said.

‘I think we played miles better in the first half than the second half, but we scored and in games like this you need a first goal to settle any doubt and then spaces will come, and it’ll flow more.

‘But I think we did OK, actually.

‘They kept a clean sheet against Palace and Tottenham, and we knew they’d be hard to break down.

‘In the end, the first time they really went for it, had a chance, counter-attack and of course that settled everything.’

Rashford’s excellent effort broke the deadlock and took the in-form forward’s tally to 14 goals – his best United return in a single campaign.

‘There will be more,’ Solskjaer said.

‘But I was really pleased with him today because he kept his body language.

‘They kept kicking him, but he got up, he played, he ran, he had chances and made movements.

‘He was a leader by the way he acted today, the way we played.

‘Good goal and a very good run and he set up Anthony for his goal, so very pleased with Marcus.’