The Argentine defender, who has been left out of their Champions League playing squad by Ole Gunnar Solskjaer, was in action for Neil Wood’s U23 side alongside Brandon Williams and Facundo Pellistri.
Although the first-half would end level at 0-0, Rojo did catch the eye of supporters by hitting the post from a Ronaldo-style free-kick before taking a shot from an extreme distance.
The 30-year-old might have impressed viewers, but he was then withdrawn at the break.
One United fan said: “Rojo did a proper Ronaldo stance for the FK with the deep exhale so weird.”
Another added: “Was so close for a goal damn.”
A third continued: “Marcos Rojo taking free kicks for the 23s is Man Utd down to a tee.”
With a fourth concluding: “Marcos Rojo taking a free kick for the U21. A sublime free kick actually.”
Rojo told infobae of his future at the club back in August: “I spoke to Solskjaer, the coach, about two weeks ago because I had to go back to England.
“He said to me: ‘Look, now the season is over and everyone has a few days off. Then we go to play the Europa League... I’m not going to count on you because you haven’t trained for four months'.”
Before adding: “My idea is also to try to stay at Estudiantes. I played a game, got injured and all of this happened."
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Solskjaer said of Rojo earlier this year before his loan exit: “Marcos is a lovely lad, he's got the fire in his belly, he's a winner and he wasn't getting enough football here.
“It was important for him to start playing. He wants to come back a fitter and better player, hopefully having played well for Estudiantes and helped Seba [Veron] and his club, and gone to the Copa America.
“So that was something we just had to do.”