The Red Devils signed Lukaku in a £75m deal from Premier League rivals Everton earlier this month after seeing off competition from English champions Chelsea.
The 24-year-old established himself as one of the Premier League’s top strikers during a three-season stay at Everton after Jose Mourinho sanctioned the Belgium international’s permanent sale to the Toffees from Chelsea in the 2014 summer transfer window.
Lukaku finished behind Harry Kane in the race to win the Premier League’s golden boot last season after a return of 25 goals in 36 games for the Merseyside outfit.
However, the new Manchester United signing is hoping to make further improvements to his game despite securing his big-money summer switch to Old Trafford.
“I am very happy now. This is the job I wanted,” Lukaku is quoted as saying by the Evening Standard.
“I have to make sure that I stay focused and have the same ambition I’ve always had. And just work hard – that’s the key to success.”
Lukaku was the second summer signing at Manchester United after the Red Devils completed a £30.7m deal to sign Sweden international Victor Lindelof from Portuguese champions Benfica.
Manchester United won the Community Shield, the EFL Cup and the Europa League in their first season under Mourinho.
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