Napoli played a great game and demonstrated it on the field of being the best team, or at least one of the best, played a clean football, I had predicted a draw but the Neapolitans immediately denied me they made their players assert better and this is not easy, Lukaku has totally dominated the game, for the next challenges they will surely be more fit and more concentrated after such a victory
Napoli has a really strong team and is proving it on the pitch in every match, they also have a significant advantage, that of playing only the championship and this affects the team's performance, they have much more time to recover physical strength and manage each match at their best. This is not the case for Inter, Milan and Juventus who have more commitments during the week
You are right, Napoli only plays in Serie-A because last season they only finished the league in 10th place, they only need to focus on the Serie-A competition to maintain the top of the standings even though below them there is Inter Milan who continues to chase and still has 1 postponed match.
By the way, today Inter Milan got big win 0 - 4 over Lecce and the match went according to what was expected where Inter Milan was able to dominate the entire match completely, there is one player who I think has decreased and that is Martinez, today he created 1 goal but overall the match that Inter Milan has played shows that it is still more impressive last season.