West Bromwich Albion striker Romelu Lukaku is upset over his injury.
The on-loan Chelsea striker has been forced out of Belgium's squad due to the knock.
"For a player like me, who mainly relies on physical qualities, it is difficult to play if you're not quite right," explains the striker.
"In the last four games I have had two starts and scored twice. It has gone well, so this injury comes at a bad time. But I am mentally strong enough to come back."