Aston Villa midfielder John McGinn is out for around the next three months after fracturing an ankle.
McGinn was forced off after eight minutes of Saturday's 3-1 Premier League defeat at home to Southampton.
In attempting a challenge, McGinn's left foot became stuck in the Villa Park turf, leading to the fracture.
Villa boss Dean Smith said: "He's on crutches. Obviously, he's very disappointed, he's got an ankle fracture.
"He's a strong character, though. He'll come back a stronger person for it, and a better player.
"For us, it's a big loss because he's a key player with the energy, drive, qualities and enthusiasm he has.
"He will be sorely missed, but it gives opportunities to others as well now. We wish him a speedy recovery."
Asked how long McGinn would be sidelined for, Smith replied: "I don't know. Hopefully as soon as possible. If I was going to guess, I'd say three months."
Smith has not ruled out the prospect of finding cover in the January transfer window for the Scotland international.
"It probably changes your stance a little bit in the market in terms of what you're looking at," assessed Smith.
"We're all aware, in losing John, how it affects the team. While it gives the other lads opportunities, we're also looking out there to see what we can improve for the football club as well."
On a positive note, Smith is expecting centre-back Tyrone Mings to potentially be in contention for the trip to Watford on Saturday.
The England international, who has been out since December 8 after straining his hamstring in a 4-1 home defeat to Leicester, is closing in on a return, although the Boxing Day game at home to Norwich comes too soon.
Yet a positive Smith said: "He will be back training on Boxing Day, and then we will see where he is for the game at Watford."
Striker Keinan Davis, who has been out for almost two months with his own hamstring problem, is in the same situation as Mings and could be available for the Hornets clash.