Middlesbrough striker Tuncay Sanli will be sidelined for six weeks with the knee ligament injury he suffered on World Cup duty last week.
The 26-year-old sustained a second medial ligament tear during Turkey's clash with Belgium last Wednesday and is likely to be out of action until the end of next month.
Manager Gareth Southgate told the club's official website: "It is a real shame for Tuncay. However, we have a lot of strength in that area and his absence will provide opportunities for other lads in the squad."
Egypt international Mido partnered record signing Afonso Alves in attack - and scored his fourth goal of the season - in Saturday's 2-1 Barclays Premier League defeat at Portsmouth.
The former Tottenham man had been at the centre of speculation he could leave the club during the summer transfer window with Wigan paying particular attention to his situation.
But Southgate said at the time he would get his chance, and his prediction has proved accurate.
Meanwhile, midfielder Julio Arca returned to action after an ankle problem picked up in pre-season in Tuesday night's 2-2 reserve team draw with Hull.
The 27-year-old Argentinian played the first half of the game, but will do well to make the bench for Saturday's short trip to former club Sunderland.
David Wheater has recovered from the bout of tonsilitis which kept him out of the game at Fratton Park, while summer signings Didier Digard and Marvin Emnes have shaken off thigh injuries and Mohamed Shawky is back in training after damaging a hamstring.
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