Manchester United need to bounce back to winning ways following last week's 0-0 draw against Crystal Palace in the Premier League.
The Red Devils produced an abysmal performance against the Eagles at Old Trafford, a display that sees United seven points away from the top four.
However, Mourinho is keen for his side to seal three points when they travel to the St Mary's this weekend.
"We need points and we have a Champions League match in December – but it is a Champion League match with a difference – we can now focus just on the Premier League, not even Cup matches yet.
"We need points, we want to improve our position in the table, we want to close the gap to the top four, we want to be smelling these positions, if not there, then just behind and smelling them for the second part of the season."
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