Lukaku notched his fifth goal of the season during a 2-1 win against West Ham United on Saturday.
"He is someone that holds up the ball and brings a lot of fear to the opposition because they always get players around him which opens space at all times," Martinez is quoted as saying in the Liverpool Echo.
"He's got power, he's got pace, he's a clinical footballer driving the ball - I've been delighted with Rom.
"I think he's doing exactly what the team needs. He's such a winner that he wants to become the best striker in the world and he's got the potential to do that."
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