"I don't think it's an opportunity because of the form United are in," said Mellon.

"I know they have a threat. We have to make sure we are ready.

"We will give it everything we have got. There is no doubt we will be up against a good side.

"Two days is enough for us to be ready..we will be fine."

Asked if he thought United were vulnerable, considering the pressure which Solksjaer is coming under Mellon added: "No. They are a fantastic football club and will come here very professional.

"I've seen the other side of that when I was at Shrewsbury and they came like robots, did the job and got out of town. I know that is the threat they possess.

"We have to go out there and understand that is what will come here. They are an unbelievable football club and we are a League One club, at the bottom end of League One, but we are going to give it everything we've got.

"We will try to represent the club again and the players will run their socks off again and who knows? What we do know is that we will be up against a formidable outfit."

Much has been made of the state of the Prenton Park pitch, it has suffered because of the weather and heavy rain forced the postponement of this replay last week.

Both wings were heavily sanded and the are a number of bald patches on the playing surface.

"A lot of hard work has gone into the pitch," added Mellon.

"Everyone complains about it and we say 'We have to play on it as well, more than you'.

"We got it on and it was a good game on there. Nigel Pearson wouldn't moan about it because he's a good guy."

To his credit Pearson, who made 11 changes from Tuesday night's defeat at Aston Villa and selected seven under-23 players, made no excuses about the surface.

"It was a tough game. We learned a lot about our young players tonight and I thought the senior players were excellent," he said.

"Congratulations to Tranmere. For people who possibly thought we weren't too interested in it, we were but we couldn't risk too many first-team players.

"It (the pitch) is the same for everyone. They showed a lot of energy and desire. In the first half we were second-best in terms of desire."