Lukaku struck twice before Arkadiusz Milik halved the deficit, but Lautaro Martinez’s second-half effort sealed the win – yet that did not stop pundit Fabio Capello labelling Inter a counter-attacking side.
Conte took exception to the analysis and also hit back at critics of Lukaku who already has 14 goals in 18 games for his new club.
Conte said: ‘I heard people say Lukaku was a donkey… I heard all sorts not even that long ago! It’s easy to speak highly of Lukaku now, but if we look back to a few weeks ago…
‘I always said Romelu was a rough diamond that needed work to smooth him out. Lautaro Martinez is the same. These lads are 26 and 22 years old, they are still young.
‘I wanted Romelu very strongly when I was at Chelsea, even back at Juventus. I wanted him, now I can get to work on polishing the diamond.’
Conte also rejected Capello’s assessment of the display and insisted his side were focused on attacking instead of just defending.
‘I don’t think Inter defended and went on the counter, as we tried to press Napoli right on the edge of their own area for the whole game,’ replied Conte.
‘I hear people always saying we play counter-attacking football, but this is a side that knows what it has to do every time it is in possession.
‘We play knowing full well everything we have to do at any moment of the match. Fortunately, our opponents respect us more than the media seem to. People say we win away because we defend deep and go on the counter, but that is certainly not our approach.’
Inter Milan are now level on points with Juventus and have regained their place at the top of Serie A with a trip to Atalanta next on January 11.
Conte said: ‘Obviously it’s an important victory, as winning away to Napoli is never easy for anyone. Napoli have in recent years been the main challengers to Juventus, with Inter a long way back, so closing that gap this season is an important step.
‘We played with character, it’s a game that gives us more confidence in what we are doing and allows us to go forward with the same courage.
‘As I always ask, we have to show courage when pressing high up the field and then defend when we need to, but that’s true of all football.
‘There are risks, as if you press high and get it wrong, that means you can leave gaps at the back and be in danger on the counter, but that is the nature of this approach, you can’t cover everything at once.
‘We could have dealt better with those situations this evening, but Napoli have this as one of their strengths, so we were bound to run a few risks here.’