Jamaal Lascelles says he cracked his tibia during the 2-1 win over AFC Bournemouth - and is now playing the waiting game.
Lascelles is expected to be out until early 2020 with the centre-back ruled out for the entire festive programme.
The former Nottingham Forest man though is staying on the positive side and has already been back in the gym
Lascelles, speaking in the club programme, said: "It's been three weeks since I picked up my injury against Bournemouth.
"And I'm actually feeling good.
"I'm able to do a lot of stuff in the gym and keep on top of my fitness and since I did it I've not really felt much pain.
"Obviously, I know at the same time there's a crack in the bone so it's just a matter of time and waiting for it to heal.
"That's the frustrating part."
And explaining the injury, Lascelles went on: "I was trying to shield the ball from Martin Dubravka and I was running full pelt.
"The striker kicked the outside of my right leg and pushed me in the back and I've jolted my leg and twisted it a bit.
"At the time I felt a sharp pain and I was aching, but I just thought it was a knock and tried to play on."
Lascelles, though, believes the injury could be a lot worse.
He added: "When I got back inside the dressing room it swelled up quote a bit and the swelling got even worse when I got home.
"In the past players have said that can be a sign of a cruciate injury.
"But luckily I went for the scan and my ligaments were fine it was just a crack in the tibia."
