Manchester United kept it tight at the back in the opening leg, but courtesy of David De Gea's remarkable precision they manage to keep the tie alive and will go into the second leg as favourites playing at home.
"I am expecting United to go through, mainly because this is the poorest Sevilla side in years".
Man United are looking to join Liverpool, Juventus, Manchester City and Real Madrid in the hat for the last eight.
The two sides played out a goalless draw in the first leg in Spain last month to leave the last 16 tie finely poised ahead of the return leg this week.
"I think we're not one of the best teams in the competition", said Mourinho.
"If we go through to the quarter-finals, it doesn't matter the opponent, it will always be one of the big names in European football, but we'll try".
United boss Mourinho is wary of the threat Sevilla pose, however, having witnessed the Spaniards - fifth in La Liga - hold Liverpool to 2-2 and 3-3 draws in the group stage of this season's competition. I say Liverpool because they are an example of a very good team, a good example of an important stadium with a big tradition.
Europa League success last season rescued Mourinho's first year in charge at Old Trafford, securing a place in Europe's premier club competition as a result.
Tonight's encounter is the first knock-out Champions League match at Old Trafford since April 1st 2014, which shows the extent of United's fall from grace in recent seasons.
Speaking to La Sexta, and covered by Marca and others, Mourinho was asked about De Gea potentially moving to Real Madrid in the summer transfer window.
"United has to be a team in the Champions League, so that victory was very important for us because we finished outside the top four".
The France global missed Saturday's 2-1 win over north-west rivals Liverpool due to a thigh injury, but Samuel Luckhurst of the Manchester Evening News confirmed he was back in the squad ahead of Tuesday.
"We don't know yet", said Mourinho.
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