Lukaku's first goal was cancelled out by a magnificent set piece from James Ward-Prowse, but Lukaku struck in the closing minutes to secure a hard-fought three points for his side.
Mourinho was sacked in December after a dismal 3-1 defeat to Liverpool at Anfield, and since replacing him with the Norwegian, United have gone undefeated domestically and catapulted themselves back into top four contention. Indeed, the symbolism of this...
"We know it's going to be hard", the caretaker manager, who was also missing defensive trio Phil Jones, Matteo Darmian and Antonio Valencia at the weekend, told reporters.
"We have done fantastically well away from home but we go to PSG with the belief, we have nothing to lose".
The ex-Arsenal man was limping heavily as he left the stadium leaving Solskjaer with more selection headaches ahead of the trip to Paris Saint-Germain on Wednesday. The Saints goalkeeper tipped a Lukaku shot around the post, did well to react to a cheeky attempt from distance by Andreas Pereira, and then saved at close range from Lukaku again when the striker should have scored.
SpaceX launches Crew Dragon's first test flight
Whichever company delivers astronauts first wins a small USA flag left at the station by the last shuttle crew in 2011. From there, the astronauts on board the space station will take over the receiving process.
"We should have been 1-0, 2-0 up in the first five minutes".
Can Solskjaer's men come back in the second period and carry on their impressive run of form?
For a long time now, Romelu Lukaku has come under criticism from the fans for his inability to convert in the penalty box.
He said on BT Sport: "I don't agree with that (Ince), because one of the most decorated managers of our generation, Jose Mourinho, failed".
Victory over Southampton - Solskjaer's 13th from 16 games in charge - would have been more comfortable had Pogba not missed a stoppage time penalty. "Everyone has got to be ready and I'm sure whoever comes in will go and do their job the best they can".
"I have to say that we felt invincible", Solskjaer said.
Under Solskjaer Manchester United have found it pretty easy to score goals and so will be confident they can find the net a few times even against PSG's superstars. The 26th minute goal changed the landscape of the game, but no one knew what they were in store for.