The Argentina international afforded himself a small celebration with his close family and friends to mark his special day ahead of their trip to Anfield on Sunday.
United midfielder Herrera, who was a summer recruit, like Rojo, from Athletic Bilbao last July, uploaded a photo with Rojo to his Instagram account on Saturday afternoon.
Herrera posted the above photo and wrote: “Yesterday afternoon on Marco’s birthday @marcosrojo”
Herrera has scored three goals and has made three assists in 17 Premier League appearances following his £29m move to Athletic Bilbao last summer.
Louis van Gaal’s side are six points clear of sixth-placed Tottenham following their win, whilst the Red Devils can extend their lead over their closest rivals Liverpool with a victory at Anfield next weekend.
However, United suffered a 1-0 defeat on Merseyside last season after Daniel Sturridge scored a fourth-minute winner against the 20-time English champions.
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