Lewandowski blanks 'no problem' for Poland coach

"The fact that Lewandowski has not scored a goal yet is not a problem for either me or the team," Nawalka told media in Marseille's Stade Velodrome on Tuesday.

"It is a matter of time, I think he will score in the next game," he said.

With two 1-0 wins against Northern Ireland and the Ukraine either side of a scoreless draw against Germany, Poland finished in second place in Group C on goal difference and play Switzerland in the last-16.

While the Bayern Munich superstar has yet to open his account, his strike partner Arkadiusz Milik scored in the win over the Irish, while Jakub Blaszczykowski scored the only goal against Ukraine.

The Poles scored 33 goals in qualifying, more than any other team, with Lewandowski taking the lead.

"He does a lot of hard fantastic work, and has a great influence on our wins and the way we play...he's like the steam-powered locomotive of the team," Nawalka said.

"He plays in a supportive way in all elements of the match, and can sacrifice his individual goods for the team".