United laboured to dispose of the Danish side in 90 minutes, with their 21st penalty kick of the season, converted by Bruno Fernandes in the 95th minute, enough to book a semi-final clash with Wolverhampton Wanderers or Sevilla, who play on Tuesday.

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Norwegian Solskjaer, chasing his first silverware as United boss, is hoping a repeat of their League Cup semi-final defeat by Manchester City and FA Cup last-four loss to Chelsea will not be repeated in Cologne on Sunday.

"We need to be more clinical in knockout games," Solskjaer said. "I am delighted we are through to another semi-final for this team and the next challenge is to go one step further, and then hopefully win the last one (the final), too.

"We have worked hard throughout the season, and come quite a distance from where we were in terms of fitness, but mentally that is where they (the semi-finals) are decided."

United's performance, however, will not give Solskjaer too much hope of going a stage further.

While United had plenty of chances, their finishing left much to be desired, as the Premier League side struggled to cope with the energy-sapping conditions.

Bruno Fernandes celebrates scoring in extra-time for Manchester United

Image credit: Getty Images

"We're used to having the best facilities around in the world for recovery and preparation," Solskjaer added. "But not this time.

"We just have to make the most out of a difficult situation in conditions that are really hot, humid.

"We’ve got six days to prepare. There’s not many times that we have six days to prepare for a game."

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