Eyebrows were raised before a ball was kicked as midfield star Ella Toone was left out of the starting XI, alongside striker Elisabeth Terland.
With goalkeeper Tullis-Joyce out and Middleton-Patel making only his second senior appearance for United – his first at Old Trafford and in the Champions League – fans were worried.
And Wales international Middleton-Patel immediately got a taste of elite level when Jennifer Echegini’s powerful shot bounced off the inside of the right post inside two minutes.
United left-back Sandberg had his hands full, with Nigeria international Rasheedat Ajibade sprinting relentlessly down the wing, and PSG dominated possession.
But in Malard, United always had an outlet.
She remained quiet until the opportunity arose for her to take on fellow Frenchman Mbock Bathy and she did not disappoint, effectively reading Jayde Rivière’s flight of the ball, using her body to hold off the PSG centre-back and shooting perfectly past Earps into the far corner.
Earps slipped to her knees in disappointment, although she could do little to stop Malard’s precise goal, and United were up and running.
PSG then showed their individual quality when Carmona took advantage of the space given to him to shoot from distance, expertly flicking the ball past Middleton-Patel, who, like Earps, was helpless.
But the near 15,000 crowd at Old Trafford found their voice in the second half as Park’s dazzling feet helped create Rolfo’s goal to make it 2-1, before Earps dived well to his left to block Malard’s dangerous effort at the near post soon after.
Despite PSG’s attempts to find the equalizer, it was United who looked more assured, proving they belonged among Europe’s elite and taking on the French giants – who have reached the semi-finals in four of the last five seasons.
England international Park was at his best, Gabby George replaced the centre-back superbly and Malard provided the necessary magic as United ensured Earps’ return was anything but celebratory.
But despite all the controversy surrounding Earps, United fans bid a fond farewell at full time as she walked into the stands applauding them – despite some pantomime boos throughout the match.
This will ring alarm bells for PSG, who have lost all three of their league stage matches this season, increasing the pressure on head coach Paulo Cesar.
