Wales captain Sam Warburton says the rugby community is rooting for his Cardiff Blues team-mate Owen Williams.
Williams, 22, has suffered a "significant injury" to his cervical vertebrae and spinal cord.
He is recovering in hospital in Singapore after undergoing an operation to stabilise a fracture.
"I'm always an optimist. At this moment in time you don't care about the rugby you just want him to be as healthy as possible," said Warburton.
"Every player was devastated at the training ground and everybody's got their fingers crossed for Owen."
The Wales centre was injured while playing for the region at the World Club 10s in Singapore.
The Blues say arrangements are being made for his "safe transfer home".
Williams' family are at his bedside, along with senior Blues officials and medical staff.
"Hopefully we'll hear some good news in the next few days and obviously our thoughts are with him and his family," said Warburton.
"We tried to send as many messages as we can out there, to get to Owen, and the whole rugby community has got behind him.
"So everybody is wishing him well and a speedy recovery."
Players from around the world have taken to Twitter to support four-times capped Williams.
British and Irish Lions and Wales full-back Leigh Halfpenny wrote: "Thoughts are with you and your family."
Australia flanker David Pocock wrote: "Owen, sending some love and well wishes from Canberra. We're all thinking of you and hoping for a speedy recovery."
Williams's brother, Gavin, tweeted: "So emotional reading all the support. It's overwhelming. In the hospital next to my brother. He's a warrior."
Warburton himself has tweeted the hashtag "#StayStrongForOws" and said he hopes the messages will encourage Williams.
"It's been incredible and I'm sure he's aware of that as well and it will give him a massive, massive boost," said Warburton.
"I've known him personally for the past four to five years he's been with the Blues and he's an absolutely incredible athlete.
"You never want to see anybody go through that.
"It's scary as a player because you know you've got as much chance, when you hit the field, of that happening to you.
"I guess everybody has that chance when you step into a car everyday.
"It's scary but you have to realise that it was just a freak accident."