At the time Lukaku was already playing for Anderlecht and a full Belgian international. Two years later he has a new Chelsea shirt and this time he is being paid to wear it.
Lukaku reminisced about that visit on Thursday after the club confirmed the completion of his transfer.
"I was 16, and already playing with Anderlecht. It was just after the season finished and I bought a shirt with my name on," he told Chelsea's website.
"I wanted to feel like a normal kid and to show the kids in my class they could accept me, that I was just a normal human being."
On the pitch, Lukaku is one of the most talked-about young forwards in European football. At 16, he finished as the top scorer in Belgium's domestic league with 15 goals as Anderlecht won the title in 2009/10.
He added another 16 last season and with his power, pace and stature has been likened to his new Chelsea team-mate, Didier Drogba. The six-foot four-inch youngster may one day replace the 33-year-old Ivorian but for now is intent on learning from him.
"We have similar playing styles, but I am also very fast," said Lukaku, whose father Roger played for Zaire.
"I want to learn off him how it is to play here at the Bridge and how to prepare for games. I can also learn off the other strikers and experienced players in the squad."
Lukaku's transfer had been announced on August 6 subject to his passing a medical and agreeing personal terms. He is now available for Saturday's Premier League home game against West Bromwich Albion but warns he is not the finished article yet.
He said: "I can improve everything - technique, speed, my finishing can be better. I just want to help the team to win games and first of all, for me as a young player, I need to learn from the other guys."
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