Jose Mourinho admits it will be "difficult" for Manchester United against Sevilla in the second leg of the Champions League round of 16 tie after the first leg in Spain ended in a 0-0 draw.

David de Gea's heroics made sure the Red Devils kept a clean sheet during their trip to the Estadio Ramon Sanchez Pizjuan on 21 February. The return leg will take place at Old Trafford on 13 March and a defeat for the hosts will end their hopes of making it to the quarter-final.

A tie ending in a draw with goals will also result in United's elimination as Sevilla will progress further on away goals rule. Only avoiding defeat will guarantee the 20-time English champions a berth in the last eight of the European competition.

"If we draw with goals in the second leg, we are out. If we win, we are through. It's difficult. I believe that Old Trafford misses a big European night. We had the quarter-finals and semi-finals last year but the Europa League has a different meaning," Mourinho explained, as quoted by United's official website.

Mourinho was also impressed with De Gea's performance against Vincenzo Montella's side. The Portuguese tactician is aware of the former Atletico Madrid goalkeeper's qualities, who was successful in negating the "mistakes" made by his teammates on Wednesday.

"I think the clean sheets are because of the team and because of David," the former Real Madrid and Chelsea manager said.

"But, we also kept a few clean sheets with [Sergio] Romero in goal, so I think the team even with a couple of mistakes, the team defended well and when we made the mistakes, obviously David was there. And that's the reason why he is what he is."

Ander Herrera suffered a "bad injury" and was forced off the pitch after 17 minutes against Sevilla. The Spanish midfielder was replaced by Pogba and the former is set to miss the league clash against Chelsea on 25 February at Old Trafford.

Jose Mourinho
Jose Mourinho says Old Trafford misses a big European night Reuters