The Czech international goalkeeper injured his calf in the later stages of the first half of the Champions League clash and was replaced by Carlo Cudicini at the interval.
Chelsea coach Avram Grant said: "He could not continue in the second half. How bad the injury is we need to wait and see. It is a calf injury and I asked the doctor if he could continue and he couldn´t. But Carlo Cudicini came on and played well."
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