The centre-forward's form and fitness has led to a debate about his situation at Napoli.
And now Lukaku's actions this week has brought more intense scrutiny over his future in Naples.
Il Mattino says the Belgium striker was expected in Castel Volturno yesterday, but he didn't show up. Lukaku chose to stay in his homeland to continue his fitness training on his own, angering management, with whom he hadn't agreed anything.
Lukaku will likely need another 7-10 days of personal time, at least that's the request he made to the club just yesterday morning.
Therefore, it's unlikely the player will be available for Napoli's next match against AC Milan - and it remains to be seen whether he'll be back in the squad against Parma.
The key influence on 'what next' will be coach Antonio Conte, who is said to have been left unimpressed by Lukaku's no-show on Thursday.