Sabres star, Jack Eichel, has a high-ankle sprain in his right leg and will be out indefinitely.
Eichel suffered the injury in Saturday night's first period against the Boston Bruins.
He lost an edge near the boards and went down in clear pain.
He suffered the same injury in his opposite leg in the day leading up to the 2016 season.
The team would go on to win Saturday night's game 4-2, but going forward this will be a huge loss for an already struggling team.
They're back on the ice Sunday night at home against Colorado.