The Chelsea striker Romelu Lukaku has launched a stinging attack on his former manager André Villas-Boas, insisting he will "never forgive" the Portuguese.

The 19-year-old has accused Villas-Boas of ostracising him from the day he arrived at the club. Lukaku was signed for £18m at the start of Villas-Boas's reign as part of a long-standing scouting project but he was hardly given a look-in.

Lukaku told Sportwereld: "There is one person that I will never forgive for what he did to me – the previous coach. It's not just that. It was also the way he spoke to me and treated me.

"Right from the beginning, it was weird. I could not stand how he was treating me. I received no explanation. In training, he put me on the right or left wing. In training matches, I was a substitute with a shirt to keep swapping teams. I really learned nothing.

"I have told the club that too. I understand that he was under pressure, but I was also thinking of myself. I have improved in recent months."

Lukaku only had a little more game time under the caretaker manager, Roberto Di Matteo, and was not in the squad for Saturday's Champions League triumph.

He was nevertheless delighted with the outcome, saying: "I could not believe it. I had to think, 'Is this really happening'? European champion ... My life has changed and I'm only 19."