Brentford striker Scott Hogan is to undergo an operation to repair his anterior cruciate ligament.
The 22-year-old, a summer signing from Rochdale, is set to miss the majority of the season after suffering the injury against Rotherham last month.
He wrote on Twitter on Wednesday morning: "Off to the hospital, get this op done and out of the way!!"
Manager Mark Warburton says the rest of the Bees squad will rally round their injured team-mate.
"He'll be well treated medically and the boys and staff will get around him. In those situations you do have some dark days, there is no denying that," Warburton told London24.
"You're stuck in the gym or in the pool or on the bike. The unity in the changing room is outstanding.
"Everyone has got to get around him. Hopefully that time flies by for him, he's a very talented player and hungry to play at the highest level and hopefully the rehabilitation will take over.
"We're not going to rush him back. He's a young player with a big future ahead of him. "