Chris Coleman has backed Duncan Watmore to return better than ever after confirming he is set to miss the rest of the season after undergoing knee surgery.
Watmore has suffered cruciate knee ligament injury for the second time in the space of a year, with the 23-year-old forward now set for another lengthy spell on the sidelines.
The forward, who had 10-months out after injuring his left knee last December, underwent exploratory surgery to confirm the club's worst fears after he went off in the recent draw with Millwall before Coleman took charge.
After returning against Preston North End in September, Watmore featured regularly under former boss Simon Grayson and re-established himself as a key member of the first-team squad.
But he suffered a recurrence of the cruciate knee ligament injury in the same knee against Millwall and has now had surgery.
"To lose a player as good as Duncan was a big blow to everybody. He has worked so hard to get back," said Coleman.
"Duncan had the surgery today. It is as we feared. It will be another long one for him.
"Forget me, us, it is about him. He is a young man and has a really good career ahead of him.
"He will be devastated. We have to take care of him as much as we can and we will do. However long it takes he will be back, I am sure about that.
"The mental side is harder than the physical side. When you do get through it, and he will, it makes you better and aware of how lucky we are of being in this industry in the first place.
"Some players don't respect how lucky they are to be playing football. No matter how hard the situation, we are playing football.
"For people like Duncan Watmore, he will respect it even more - not that he doesn't now because he is a good kid - but he will respect it even more.
"He will be better when he gets back, I am positive about that.
"This season probably won’t happen for him.
"I told Duncan on Sunday, if it’s bad news then the worst thing you can do is put a time on it, but he’ll be chasing time as he’ll want to be back.
"Life is frustrating sometimes as he’s desperate to play football and desperate to play for Sunderland."
Sunderland had 10 players missing for the 2-1 defeat to Aston Villa and Coleman says the focus has to be on those players that are fit while challenging others with shorter term injuries to make a speedy recovery.
Jonny Williams is out for between a month and three months after undergoing shoulder surgery, while Lamine Kone and Billy Jones are both out with knee injuries. Marc Wilson (calf) and Jack Rodwell are also among the injured players.
On the injury problems, Coleman added: "That is what happens when you are in these positions, one piece of bad news after another. Nobody else will change it for us. It will be us and it has to come soon.
"The players that are injured, some are longer term injuries than others. They can't help us now.
"They are part of the club, of course, but let's see how determined they are to get back on the pitch.
"The players we have fit, it is all about them, preparing them properly and making sure they give us their best.
"Some of the boys who are out for six or eight weeks, let's see if they really want to get back and help this situation.
"We will see how that progresses."