Dan Vickerman's former Wallaby teammate Jeremy Paul is one of many who have paid tribute to the 37-year-old following his death.
The Australian Rugby Union (ARU) confirmed Vickerman died at his family home in Sydney overnight. It is understood there were no suspicious circumstances.
Born in South Africa, Vickerman moved to Australia at age 21 and went on to play 67 Tests for his adopted nation from 2002-2011.
Paul played alongside the second rower at the ACT Brumbies and for the Wallabies, and was in shock after hearing the tragic news.
"It's really shocking to be honest, 37 years of age and he had such a life to live ... all of our hearts and well wishes go to (Vickerman's wife) Sarah and their two little kids, it's a big shock," Paul said on Fox Sports News.
"Our hearts are just with Sarah and the two little kids his family, it's a really shocking time for everyone.
"It's just shocking. It's pretty hard to take in actually."
One of Vickerman's most endearing qualities, according to Paul, was his sense of humour.
"He was just one of those really good characters you love having around. His wit was so dry, being South African, and he always made us laugh that's for sure. It's just such a shock," he said.
"He was just one of those great characters, you could always count on Vicks saying something really dry with his humour because that's the sort of guy he was. He'll be sorely missed."
As an on-field talent, Vickerman will go down as one of Australia's best locks. He moved to Australia in 2000 and won the Super Rugby title with the Brumbies the following season, before making his international debut in 2002.
"He was just so tenacious, he was one of the biggest competitors. On the field he was just such an angry guy. As a teammate that's what you wanted, someone who would go into the trenches with you," Paul said.
"He always played consistently well, he was a guy who strived to be as good as he possibly could.
"(Former Wallabies coach) Eddie (Jones) used to ride him, God he used to give it to big Dan, but Dan took it on and he turned into a Wallaby and a great Wallaby, and a great Brumby and a great Waratah.
"He was so big, he had such a presence on the field."
Plenty will be in mourning the loss of Vickerman, but Paul wanted to make sure the aftermath of his death was also used to remember just what made him such a special person.
"It's an opportunity to talk about how good of a human being he was and how good a rugby player he was. When everyone goes to his funeral later this week it will be spoken about just how great a guy he was and his memory will be passed on forever," Paul said.
"Now it's time we band together and be there for Sarah and their two kids, helping them get through this period of heartache, (we're) hurting so much, we want to make sure his memory lives on forever."
SPORTING COMMUNITY REACTS
Rugby players, former rugby league players and cricketers all expressed their sadness at news of Vickerman's passing.
Former Waratahs and Australia teammate Phil Waugh had only positive things to say about his good friend.
"We all have huge admiration for the guy that he was," Waugh said, per Fairfax Media. "He was one of those players when you're standing next to him in the change room and he's running out next to you, you had so much confidence.
"He's a guy that necessarily wasn't the loudest in the team, but had the most respect from everyone playing with him. There's so many positive memories of him on and off the field."
Shocked an old team mate Dan Vickerman has passed away..Grateful to have played along side you..Thoughts & prayers are with his wife & 2kids— Quade Cooper (@QuadeCooper) February 19, 2017
Dan Vickerman ?!?! Shocking news— Ruan Smith (@Ruan_Twin) February 19, 2017
Sincerest condolences to the Vickerman family and all his friends following the passing of Daniel overnight. R.I.P pic.twitter.com/qPZ9rlwhZ5— Clint Newton (@c_newton11) February 19, 2017
Sorry to hear about the passing of former bishop boy and wallabie dan vickerman! Only 37yrs old. thoughts are with his family and friends.— Herschelle Gibbs (@hershybru) February 19, 2017
Waking up to sad news about Dan Vickerman this morning. Always enjoyed playing against him. A real competitor and a great guy.— Victor Matfield (@VictorMatfield) February 19, 2017
Incredibly saddened waking up to the news of Dan Vickerman. A true gentleman of the game. Thoughts are with his family.— Adam Ashley-Cooper (@AdamCoopy) February 19, 2017
Rest easy Vicks
Thoughts and prayers with the Vickerman family and their loved ones this morning. Such sad news to wake up to— Bryan Habana (@BryanHabana) February 19, 2017
'HE CARED DEEPLY ABOUT THE GAME AND THE PLAYERS'
ARU CEO Bill Pulver said Vickerman will be remembered for his love of the game and his fellow players.
"The rugby world is in shock today after news of the tragic passing of Dan Vickerman," Pulver said. "Dan was an uncompromising competitor who forged a wonderful international rugby career despite a number of injury setbacks along the way.
"He was an enforcer on the field and a much-loved character off the field. He cared deeply about the game and the players, helping players transition into life after rugby in his role with the Rugby Union Players Association (RUPA) following his retirement.
"Our thoughts and prayers are with Dan's family at this extremely difficult time."
RUPA CEO Ross Xenos said Vickerman's contribution to the sport even after he'd retired showed they type of selfless person he was.
"On behalf of all players, we extend our deepest sympathies to Dan's young family at this difficult time. We are truly shocked and united in our despair," Xenos said.
"Dan was universally respected by his peers and the rugby community during and beyond his playing days.
"Since retiring, he was very generous in giving back to the game through coaching and voluntary roles supporting players' off-field development.
"We encourage all players who are affected by today's terribly sad news to support and be there for each other and to contact RUPA if they would like to talk."
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