The 30-year-old Togo international was admitted to hospital on Saturday after reporting feeling unwell.

"A swift diagnosis meant the disease was detected at an early stage and he is responding well to treatment," said a club statement.

"The striker is expected to be released from hospital on Monday and will then require a minimum of seven days before returning to training.

"The player has been advised not to travel on medical grounds, which means he will be forced to miss our pre-season tour of North America."