The 28-year-old, who struck 15 goals in 32 league games last season, will have surgery today on a persistent calf injury and will be in plaster for six weeks before beginning his recovery. It means he will miss the UEFA Champions League third qualifying round next month and, almost certainly, the entire group stage should the Belgian champions progress.
"This is a shock," said Lange. "I didn't think it would be so bad, especially as I was still able to walk.
I am paying the price for the end of last season, when I forced myself to play because the championship and cup final were at stake. I hope I can play some matches before the new year, but to be honest I am aiming for the second half of the season."
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