Belgium manager Roberto Martinez has heaped praise on the development of Dries Mertens into a "master of the number nine position".

Gonzalo Higuain's move to Juventus last summer saw Napoli boss Maurizio Sarri move Mertens into a more central and advanced attacking position, and the Belgian responded with 34 goals and 15 assists in 46 matches this season.

Belgium already have the likes of Romelu Lukaku, Christian Benteke, Michy Batshuayi and Divock Origi vying for a striking role, but Martinez is happy to have a new option in the form of Mertens.

"Both Mertens and Radja Nainggolan have reached a level of maturity. The way Mertens is playing as a number nine is remarkable. To watch him play for Napoli with Jose Callejon and Lorenzo Insigne is a feast for the eyes," he told reporters.

"I was in the stands for their game against Inter and the way of interpreting the new role and his movement were just fantastic. Dries has proved he can play in several different positions, he can make the most of spaces and is an intelligent player.

"In this new role as a striker, he represents an extra option for us, having become a real master of the number nine position."

Belgium take on Czech Republic and Estonia next week.