Romelu Lukaku has fired back at pundit Gary Neville for questioning his professionalism, citing the praise of his former coaches as proof of his commitment to the game.
Lukaku completed a £74 million ($90m) move to Inter this summer, bringing to a close a two-year spell at Manchester United that was filled with ups and downs.
The Belgian was subject to criticism on the way out, with former United player Neville tweeting Lukaku, having admitted to being overweight “will score goals and do well at Inter Milan but unprofessionalism is contagious!”
And Lukaku, who opened his Serie A account in his debut with Inter last week, took exception to the tweet, saying one only has to look to the long list of managers who have praised his work ethic to see how wrong Neville is.
"Don't question my professionalism," Lukaku told BBC Sport. "I live for this game. I am at home all the time. I try to do everything to improve."
"He (Neville) can talk about my fitness but he should never say anything about my professionalism, that I don't work hard enough. That is something he cannot say. All the coaches I have had say the same thing about me.
"What did Ole Gunnar Solskjaer say when I was on the training ground? What did he say? That I always work hard and always do my best to try and improve myself. Same with Jose Mourinho and Roberto Martinez. Now Antonio Conte will say it.
"Last year was just a bad year. It happens in football. You just have to move on. I am not going to sit here and react in a negative way.
"We are grown men. He is a pundit. He gets paid to say this kind of stuff. I am paid to play football. I just want to do my best for Inter Milan. That is it."
Lukaku also moved to deny any fitness issues during this past pre-season with United – which had been used as justification as to why he did not see the field.
The striker started for Inter in their 4-0 win over Lecce in the Serie A opener, going 90 minutes, and discussed the high levels of fitness required to play in head coach Antonio Conte’s system.
"I was training by myself for the last couple of weeks in Manchester with one of the physical coaches," Lukaku added. "From Singapore until I moved here, I was basically only doing running and not training on the pitch. When I got here they asked me what I had been doing.
"I had not done any group training, only running, so we kept the running part going. They introduced me to the group exercises and then they organised some friendlies and that was it.
"When I arrived, the first four days were about building up the physical aspect, getting as fit as possible for the first game - do a lot of physical work and adapt tactically to what he (Conte) wants on the pitch.
"How we play involves a lot of pressing, being in the right positions. You have to be alert and sharp in training."
When asked if he knew why United thought he had a fitness issue, Lukaku told BBC Sport: “No.”