With the Red Devils currently sitting sixth in the Premier League table, winning the Europa League represents an alternative route into the Champions League for United, and Mourinho is eager to keep both options open.
"We go home with a positive result. We know that it will be a difficult match, we know that we need to win or to have a 0-0 draw, so the game is open. The tie is open, but in these circumstances I think it was a positive result. An away goal is always positive. It is better 1-1 that 0-0, obviously. But the game is open, the result is open and this Rostov team have experience of playing big matches, big opponents, big stadiums," he told reporters.
"I don't think it is a problem for them to go to Old Trafford and to compete against us. They play Sunday against Terek Grozny, we play Monday against Chelsea. Who knows, we could have extra time and 30 minutes more to play, so for us it is difficult. But we are one step from being in the quarter-finals, the players have that motivation. The fans for sure at Old Trafford will push with us. Hopefully in one week's time, we go to the quarter-final.
"We want to keep the two doors open. We have to keep getting points in the Premier League to let us go to the last months of the competition with that door open. In the Europa League, if we manage to go through this knockout round, we go to the quarter-final and then you feel that the door is open. So we have to try, we have to try by every means. We have a trophy in our pocket, which is always a good thing, a good feeling for everyone."
United are back in action on Monday when they take on Mourinho's former club Chelsea in an FA Cup quarter-final.