Mertens returns to Belgium for physio on ankle injury

The 33-year-old limped off during Napoli's 1-0 defeat at Inter Milan last month with a sprained left ankle.

Mertens returned to action in mid-January but has struggled for form and was unable to finish this week's 4-2 Italian Cup quarter-final win over Spezia after coming off the bench at half-time.

"Mertens returned to Belgium to carry out a course of physiotherapy on his left ankle," the club said in a statement.

He will return to the centre where he was already treated last month, the team added.

Mertens has scored 130 goals for Napoli since signing from PSV Eindhoven in 2013, including five this season in all competitions.