Louis van Gaal’s side clinched their second win of the Premier League season against the Hammers at Old Trafford thanks to goals from Wayne Rooney and Robin van Persie.
The three points hoisted the Red Devils up to seventh place in the top-flight table.
And Rojo posted a picture of himself out for dinner with his girlfriend Eugenia following the victory at Old Trafford.
Rojo, who joined United from Sporting Lisbon in the summer, wrote: “Having dinner with my loves @eugelusardo.”
The Argentina international had earlier praised United on Instagram for taking the three points despite being reduced to 10 men against the Hammers after Rooney’s red card.
He wrote: “Very difficult game but we achieved our objective. Congratulation to my team mates.”
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