Boro have confirmed that Tuncay Sunli will be sidelined for around six weeks.
Tuncay suffered knee ligament damage while on international duty with Turkey last week and is not expected to return to first team action until the end of October."It's a shame for Tuncay," Boro boss Gareth Southgate told club's official website.
"However, we've got strength in depth in that area now and it gives opportunities to the other lads."
