The Belgium striker arrived at Old Trafford as the club’s second signing of the summer back in July when he completed his switch from the Merseyside outfit.
The move came as something of a surprise, because Chelsea were being heavily linked with a bid to land Lukaku before he eventually ended up signing for the Red Devils.
Henry knows Lukaku well having coached the 24-year-old forward as part of his role with the Belgian national team.
And the former Arsenal star is tipping the Belgian forward to be a big hit and bring goals to Jose Mourinho’s team next season.
Speaking in an interview with Sky Sports, Henry said: “What I can say about him is that he is a massive student of the game.
“Everything he does, he does at 100 per cent. I’m as excited as anyone to see how good he is going to be at United.
“It’s definitely a plus to have a guy like Romelu in your team. Anything that drops in the box is usually a goal.”
Manchester United are currently preparing for their Premier League opener against West Ham United at Old Trafford on Sunday afternoon.
Lukaku scored his first competitive goal for Mourinho’s men in the 2-1 defeat by Real Madrid in the Uefa Super Cup on Tuesday night.
Manchester United have also signed Victor Lindelof and Nemanja Matic this summer as Mourinho gears up for his second campaign in charge.
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