The striker opened the scoring in the 3-0 win over Partizan Belgrade to maintain his record of finding the net in each of his three first-team starts at Old Trafford.
It was another cool finish by the homegrown youngster, who has been named in the England Under-21 squad for their games against Albania and the Netherlands.
Greenwood recently signed a new contract but his development will not be rushed. He has played a couple of full games for the Under-23s and Under-21s recently, scoring in the Premier League 2 victory over Stoke City early on and bagging an injury-time winner in the Leasing.