The Tottenham youngster, 20, picked up the knock during pre-season training in Belgium but Ling has been quick to play down the seriousness of the problem.
"Fortunately it isn't a bad twist. Hopefully with a bit a treatment he should be back in training soon," he said.
"We're doing fairly well on the injury front at the moment, as Sean Thornton is over the virus he picked up.
"Wayne Gray, Tam Mkandawire and Alton Thelwell are back in training as well. Wayne's probably the closest to returning although all three are still a long way behind the other players in terms of fitness."