Everton boss Roberto Martinez has lavished praise on Romelu Lukaku and claimed that the Belgian now has the fitness to continue at a high level for a full 90 minutes.

The 22-year-old has scored 13 times for Everton this season, including six goals in his last five matches.

The striker will make his 100th appearance for the Toffees in Monday's Premier League match with Crystal Palace and Martinez has said that the former Anderlecht youngster now has the fitness levels needed to be a force for a whole season.

"Every foreign player has to adapt to the physicality of the Premier League but, for a striker like Rom, with his frame, I don't think he had the opportunity to play enough 90 minutes when he first arrived," Martinez told reporters.

"He had an incredible scoring ratio at West Brom but I think he played only seven full 90 minutes that season. It's a long process to get to the stage where you can play 90 minutes without losing the power and the pace in every action but now it's very rare that you don't see him finish the last 10 minutes with the same power, pace and control.

"On top of that, he can play three games in a week, which is quite remarkable for a player of that size. I would say that's happening now for the first time this year. At the start of last season, he was catching up after the World Cup. From January, he's been the mature Rom who can play 90 minutes."

Lukaku joined Chelsea from Anderlecht in 2011, but did not score a single goal for the Blues before eventually leaving for Everton in 2014 following a loan spell at Goodison Park.