Christian Lealiifano is undergoing treatment in hospital after the Australia back was diagnosed with leukaemia.
The 28-year-old centre has played 19 Tests for the Wallabies, and started all three Tests against the British & Irish Lions in 2013, making his debut in the first clash in Brisbane.
Lealiifano has also been a key contributor for the Brumbies in Super Rugby, having scored 803 points in 117 matches so far, but will now be out of action for an extended period after his diagnosis.
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“At the moment it's just a matter of ensuring Christian receives the best care and support he can at this time,” said Phil Thomson, Brumbies interim Chief Executive.
“He is one of the most respected players within this group and this news has come as a huge shock to all of our players, coaches and staff.
“Everyone knows that Christian is an amazing young man, an important member of this team and of the Canberra community.
“Our thoughts and prayers are with Christian and his family at this time.”
Worldwide support
Lealiifano’s maiden Test against the Lions was probably not the debut he had dreamed of, as he had to be replaced after one minute with the tourists going on to win 23-21 at Suncorp Stadium.
But the No.12 was the scourge of the Lions in the next game, notching a perfect four kicks from four to score 11 points for the Wallabies in a 16-15 win.
And while Lealiifano managed the same number in the decisive Test, again being flawless off the kicking tee, the Lions were rampant and wrapped up the series 41-16.
Several Australian stars have commented on social media following the news, with the likes of James Horwill, who captained the 2013 side against the Lions, and Brumbies team-mate David Pocock offering their support, while many other players from around the world have also reached out to the 28-year-old.
“Devastating to hear the news about Christian Lealiifano,” tweeted Horwill. “Stay strong brother, everyone is behind you.
Pocock said: “Really tough 24 hours trying to come to terms with news about Christian. One of the most respected and loved players I've played alongside.
"I know he'll be strong through this and Brumbies family will be supporting him and his family however we can."
Devastating to hear the news about @CLealiifano. Stay strong brother, everyone is behind you. #FCancer #Bruzzy
— James Horwill (@JHorwill) August 6, 2016
Really tough 24 hours trying to come to terms with news about Christian. One of the most respected and loved players I've played alongside.
— David Pocock (@pocockdavid) August 6, 2016
I know he'll be strong through this and Brumbies family will be supporting him and his family however we can.
— David Pocock (@pocockdavid) August 6, 2016
Devastated to hear the news of one of the nicest guys you'll meet. Thinking of you @CLealiifano ?
— Dan Carter (@DanCarter) August 6, 2016
Thoughts are with you fella @CLealiifano
— Jamie Roberts (@Jamiehuwroberts) August 6, 2016