The Spanish shot-stopper turned 24 on Friday and Rojo was one of his first team-mates to mention the goalkeeper on social media.
Rojo posted the picture above of the duo and wrote: “Feliz cumpleaños amigo / happy birthday my friend @d_degeaofficial.”
The defender is currently sidelined after being forced off with a shoulder problem during last weekend’s derby defeat by Manchester City, although it is not clear how long he will be out of action.
Rojo, who joined United from Sporting Lisbon in the summer, has made seven appearances in the Premier League so far this season.
De Gea, meanwhile, has played in all 10 of United’s top-flight games this season.
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