The Argentina midfielder, 31, was recalled to the starting XI and was outstanding on the day.
And Rodriguez says the victory was a career moment for him, having grown up dreaming of playing and winning at Old Trafford.
He posted to social media: "It was about three months without playing... and after so much endurance and effort, today was a reward.
"Better days, worse days, and today I was able to let out what was inside me.
"Little Guido, who watched the Premier League and Old Trafford games at home on Sunday mornings, dreaming of being a soccer player one day, would be very proud of what he became, of what he achieved with his drive and dedication.
"Of how he enjoyed and continues to enjoy the process.
"Of how he cried after the game. And of how he continues to pursue and work for his dreams."