United did not produce a good performance in the first leg of their tie against Sevilla and were heavily indebted to goalkeeper David De Gea for keeping the score at 0-0.
Mourinho said: "For sure this stadium has missed knockout football in the Champions League".
But they've come back to Old Trafford with a 0-0 draw and Mourinho knows how to win European competitions. Leaving many with the suggestion that all might not be well between the two at Manchester United.
Mourinho's men have been written off at various points this campaign and major questions were asked and decisions queries ahead of each of their last three league games. "I think we are not one of the best teams in the competition, but I think when a team arrives in the last eight anything can happen".
Against Liverpool on Saturday, Mourinho reverted to his much revered 4-2-3-1 formation, pitting Scott McTominay and Nemanja Matic together as the two defensive midfielders, while Alexis Sanchez was utilized as the attacking midfield man.
UK's sluggish economy to grow a bit more quickly: Hammond
While Hammond was arguably making more of the upgrade than it's worth, we could hardly have expected him to do anything different. In the absence of tax and spending measures, Hammond will speak about economic forecasts put together by the OBR.
Tuesday's other Champions League clash sees AS Roma host Shakhtar Donetsk at the Stadio Olimpico.
Sevilla's best chance of advancing to the quarter-finals could be to prey on any nerves there may be at Old Trafford.
The 36-year-old, who joined Manchester United from Tottenham Hotspur in 2006 for an £18m fee, became a mainstay in his side over the years and has a decorated trophy cabinet - winning five Premier League titles, one FA Cup and one Champions League trophy.
The fashion in which it was achieved irked fans but they've had some results to savour since then with 2-1 victories over Chelsea and Liverpool.
Do you think that Manchester United could go all the way in the Champions League?