Mourinho believes they are still some way off the European elite, but believes from his experiences of winning the competition with Porto and Inter Milan, anything is possible if they make the last eight.
"It's a pity that the manager is Mourinho because normally, he's an English player". But Mourinho is not like that. "But when you draw away even though it's a 0-0 - and that's not an especially good result - but we get to decide the tie at home, we don't have to win three, four, five, we have to win 5-4, 8-7, 2-1, 1-0, not to win the tie be disappointing".
Mourinho confirmed Paul Pogba is a doubt for Tuesday's Champions League game against Sevilla after picking up an injury in training last week, as he suggested his side's victory over Liverpool will count for little unless they back it up with wins in their next two games.
"If you go to his numbers and how many games he played with me".
This comment clearly got under Mourinho's skin, and he fired back with interest, taking care to mention De Boer's short-lived and disastrous tenure as Crystal Palace manager earlier this season.
"I read some quote from the worst manager in the history of the Premier Leauge, Frank de Boer", Mourinho began.
"But if he was coached by Frank he would lose because he lost every game". I try to give the best to the kid. I have to be honest and give the credit to the people of the academy that were responsible for his formation, and to Mr (Louis) Van Gaal who was responsible for his first season.
"Tomorrow is a very hard match, playing against a team that didn't lose against Liverpool home or away [in the group stage], that drew in Liverpool and I say Liverpool because they are an example of a very good team in a big stadium with a big tradition". And Marcus is having these experiences. He was saying its not good for Marcus Rashford to have a coach like me. He starts some and comes from the bench in others. "I'm really happy with Marcus". Of course not but he is a player that we trust. It was his first Premier League start of 2018 and he has played less than 100 minutes so far this year, leading many to question if his development is being disrupted.