The Belgium international moved to Manchester United in a £75m deal from Premier League rivals Everton in the summer transfer window despite interest from former club Chelsea FC.
Lukaku scored 10 times in his opening nine games in all competitions in a Manchester United shirt to hit the ground running in spite of concerns over his ability to play for a top team.
The 24-year-old striker required another 29 games to score his next 10 goals for Manchester United to prompt some criticism of the Belgian forward.
Lukaku has answered some of his critics with a goal and an assist in a 2-1 win over Chelsea FC before the centre-forward impressed in a 2-1 victory over Liverpool FC at Old Trafford.
Former Reds captain Souness explained how Lukaku can become a top striker for Manchester United after he netted again in the FA Cup win over Brighton on Saturday.
“It’s about using his brain and his physicality,” Souness told Sky Sports. “Using his assets.
“He is the strongest man on the pitch. He can get in a race with someone. Centre-halves won’t enjoy playing against him.”
Lukkau scored 25 goals in 36 games in the Premier League for Everton last season to earn a move to Manchester United.
The Belgian forward is the second-most expensive signing in Manchester United’s history.
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