The Australian Rugby Union says it is shocked by the death of the former Wallabies lock Dan Vickerman.
The Union says Vickerman passed away at his family home in Sydney overnight.
He was just 37 years of age.
It is understood there were no suspicious circumstances. He leaves behind a wife and two young children.
The giant lock played 63 Tests for the Wallabies in an international Rugby career spanning a decade from 2002-2011.
His final Test appearance was the 2011 Rugby World Cup semi-final against New Zealand in Auckland.
Born in Cape Town, South Africa, Vickerman moved to Australia with his family as a 21-year-old when he linked with the Brumbies and made his Super Rugby debut in the 2001 season.
In June 2002 he made his Test debut in a 31-25 Wallabies victory over France at Stadium Australia.
After three seasons and 33 appearances for the Brumbies, he was signed by the Waratahs in 2004 and played five seasons and 53 matches in the sky blue jersey.
After playing in his second Rugby World Cup in 2007, he withdrew from international Rugby for three years to study in England.
Vickerman earned a degree in Land Economics from Cambridge University and played in two Varsity matches whilst studying at the University, captaining the side to 31-27 victory over eternal rival Oxford in 2009.
Whilst in England he also had a short stint with Premiership club, Northampton Saints, with whom he played four matches in the 2009-10 seasons.
The 204cm powerhouse then returned to Australia to continue his career with the Waratahs and Wallabies, earning a place in the Wallabies 2011 Rugby World Cup squad.
He was forced to retire from the game through injury in 2012.
The union's chief executive, Bill Pulver said Vickerman was an uncompromising competitor who forged a wonderful international Rugby career.
"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 RUPA (players association) following his retirement.
"Our thoughts and prayers are with Dan's family at this extremely difficult time."
The players association CEO, Ross Xenos said Vickerman was universally respected by his peers and the rugby community
"Since retiring, he was very generous in giving back to the game through coaching and voluntary roles supporting players' off-field development."
Photo: Photosport Dan Vickerman at the 2011 World Cup.
Photo Below: Photosport (Dan Vickerman during the semi-final of the 2011 World Cup).
