Louis van Gaal has said Manchester United's players need to ignore the haters, as their performances have been hit by the intense scrutiny critics have put them under this season. United's fans have had plenty of reasons to be disheartened this campaign, being six points away from the Champions League places and having recently lost 2-1 to Danish outfit FC Midtjylland in a Europa League first leg.

"I think maybe it can be an influence because there's a lot of criticism so it can influence them but they have to use their tools to ignore all the criticism because that is very important. Not only important about the criticism on the manager but also on the self," Van Gaal told reporters.

Midfielder Juan Mata insisted he was not influenced by the criticism, but admitted he understands the frustrations of the supporters.

"I was very, very sad and frustrated because of the game and because of the result and because of our away fans, but not because of the media criticising," Mata said on the eve of the second leg against Midtjylland at Old Trafford.

With breaking into the top-four in the league looking less likely by the minute for United, Mata wants to qualify for the Champions League next season by winning the Europa League. Van Gaal confirmed that United will be without first-choice goalkeeper David de Gea, but long-term injury absentee Marcos Rojo is likely to feature for the first time since undergoing shoulder surgery in November.