Borussia Dortmund defender Neven Subotic will miss the remainder of 2015-16 due to thrombosis in his arm.
Subotic cannot take any part in contact sports as he recovers from the issue, even though he will be able to train individually in order to stay fit.
"Under the circumstances I am doing relatively well," the centre-back commented on his injury.
"I can stay fit with individual training and when I have recuperated again I will be in better physical condition than ever before."
The defender's absence means Slovenian youngster Jon Stankovic will make the step up from the reserves for the remainder of the season.
"We will promote Stankovic from our Under-23 squad to take Subotic's place in the squad following his absence," stated Tuchel at a news conference.
