Roberto Martinez on the key message he keeps delivering to Romelu Lukaku in Everton training

Romelu Lukaku has netted 13 goals in 18 games for Everton so far this season.

Everton boss Roberto Martinez has told the Belfast Telegraph that he keeps on reiterating to Romelu Lukaku that he must continue to work hard.

Lukaku has been in blistering form so far this season, but Martinez does not want the striker to think that he is the finished article.

As a result, the Spanish boss has been working hard with the 22-year-old on the training field – and he has been encouraged by the powerful forward’s mentality so far.

"I encourage him to keep working hard and make a massive impact in the game and I think he is in the same wave of thinking," Martinez told the Belfast Telegraph.

"You are not motivated by records you are motivated by winning games and keeping your place in the side."

Lukaku has been a prolific scorer in the Premier League for the past three seasons, despite his tender years, but he seems to have developed into the complete forward this time around.

The Belgian international has tormented defences, who have not been able to live with his pace and power.

Lukaku has netted 13 times in 18 club appearances this season, and his good form has been a major reason behind the Toffees’ impressive start.

Everton have built their success around the quality of their attack – and Lukaku has thrived off the high-quality service he has received.

The Toffees' next match comes against Crystal Palace on Monday night, and a win could lift them up to sixth in the Premier League table.

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