Morgan Schneiderlin enjoyed one of his best performances in a Manchester United shirt on the pitch at City and his girlfriend seemed particularly pleased about his role in the victory.
The France midfielder's partner, Camille Sold, was in attendance at the Etihad Stadium for United's first win on City territory for more than four years and posted a video of jubilant Reds at full-time.
Stood in the second tier, Miss Sold uploaded a video on her Instagram account of her celebrating with United fans after the final shrill.
Miss Sold proved her matchgoing credentials by adding a picture of her with a Schneiderlin scarf, reassuring Reds she does not go for half and half scarves.
"Always support my babe even if he has big ears on this scarf," she wrote.
Manchester City 0-1 Manchester United
Finally, she posted a picture of the Manchester sunset in Eastlands, as United fans jauntily walked out of the ground.
United manager Louis van Gaal was full of praise for Schneiderlin after the derby win.
He said: "I don’t have to say that too loud because the last time I said I am very happy for Morgan Schneiderlin, after that he played not so well.
"But today he played a very good match. He was a lot of times available to receive the pass but also defensively was very firm and strict and he played also a very important position in midfield. I was very happy especially because I had to rotate. Fellaini could not play the fourth game in a row."
Schneiderlin was named man of the match in United's win over Watford earlier this month but was benched for three of the next four games, with his only start coming in the Europa League surrender at Anfield.
United lost against West Brom and drew with West Ham and Liverpool, but the £25m midfielder returned to the line-up at the expense of Marouane Fellaini at City and played a key role in the winner, feeding the ball to Juan Mata before the Spaniard assisted Marcus Rashford's strike.