The £75 million signing got off the mark in United's win over Real Salt Lake on Tuesday.
Manchester United manager Jose Mourinho on Tuesday said he likes everything which new signing Romelu Lukaku does, adding that the winner he scored against Real Salt City in his football club's 2-1 win did not matter much.
"I think it's just nice for him but not important for me. When he came (over to the touchline) for the water, before he scored the goal, I told him, 'I love everything you do on the pitch'," Mourinho told Manchester United's official website.
“Don't be worried about scoring or not scoring because it's not important. He holds the ball so well, he plays one touch, two touches so well. He sees, he moves, he gets behind people, he attacks crosses, he works with the team and when we lose the ball he presses well.
"I like everything he does. For me, it's easy to feel it, because he was my player four years ago or something like that, his evolution was great. He's now a top striker and the goal is just a detail, not important," the Portuguese said.
Mourinho fielded two teams, changing all eleven players at halftime. Besides Lukaku's winner, Henrikh Mkhitaryan scored the first one for the Red Devils.
United were dealt double blows in the second half when Juan Mata and Matteo Darmian picked up knocks in the second half.
At the post-match press conference, Mourinho said: "Mata has a big ankle but I hope it is not important. A few days, a week, probably. Darmian's problem is not an important one."
Mourinho said the pre-season results hardly matter and it's more about development of players.
"This is pre-season, the results are not the most important thing. We fly the same day, we go back in the same day and in three days we are playing again. That's pre-season. People sometimes focus too much on the results," he said.
"I never do it if the results are good, if the results are bad. I just want to train and to develop the players and give them minutes to play and obviously the other game had better conditions to be a better match than today, especially because they changed the team twice.
"I really liked the first 30 minutes against their best team but in the second half they changed again and again and the boys who were playing were more on the run and in the fight than in the play but it's okay, it's an experience."
Asked about Inter Milan's Croatian winger Ivan Perisic, who is in talks with United, Mourinho said: "No idea, no idea my friend."
United next play against English Premier League (EPL) rivals Manchester city in the International Champions Cup in Houston on Thursday.