Borussia Dortmund may have to make do without the services of their leading goalscorer Robert Lewandowski for Wednesday's Champions League semi-final opening leg against Real Madrid.

The 24-year-old is struggling with a thigh injury that he picked up during the closing stages of his side's 2-0 win over Mainz 05 at the weekend.

"I felt pain in the last minute. All I can do is apply ice to the thigh and hope it doesn't swell anymore. It's touch and go whether I play on Wednesday," said the Polish international.

Lewandowski has scored 31 goals in all competitions this season, including six in the Champions League.