Leeds United defender Robin Koch will have surgery on Tuesday on the knee injury he aggravated against Chelsea.
The defender was substituted after nine minutes of his side's 3-1 Premier League loss at Stamford Bridge on Saturday.
A Leeds statement said the 24 year old German international had initially injured his knee during his debut against Liverpool in September.
"Unfortunately, following a collision in the Chelsea game, he suffered further damage to the knee," it added.
"Surgery is required to remedy the problem."
