After his success on-loan at West Bromwich Albion, Lukaku is ready to make the step up.
"I will with every part of my body workout twice as hard as last year," he wrote on Facebook. "I'll be stronger, faster and have more skills. Like the great masters of the game. It is difficult, but if you work hard you play hard.
"The season 2013/14 is the season that I stop playing as a boy, I'm going to play like a man."