World Cup-winning coach and former Brumbies mentor Jake White joined ex-Canberra players Nic White and Jesse Mogg in sending their support for Lealiifano.

Lealiifano, known as Bruz by his teammates, was diagnosed with leukaemia three weeks ago and is in hospital as he undergoes chemotherapy.

Lealiifano's shock illness hit home around the rugby world and players from different countries and clubs have flooded Lealiifano's inbox with support.

Wallabies Matt Toomua, Matt Giteau, David Pocock, Will Genia and Scott Sio shaved their heads before Australia's Bledisloe Cup clash against New Zealand on Saturday night. Toomua wrote "4 Bruz" on his wrist for the clash.

Lealiifano's situation has broken down fierce rivalries, with New Zealand coach Steve Hansen taking time in a television interview to send his best wishes to the Brumbies playmaker.

Hansen briefly put aside his team's fierce rivalry with Australia in a pre-game interview with Fox Sports to send a message to Lealiifano, recently diagnosed with leukaemia.

"Just before I go. Chris if you are out there watching this, from the All Blacks, we just wish you a speedy recovery, mate, and we are thinking of you," Hansen said.

Brumbies scrumhalf Tomas Cubelli also shaved his head before the Argentinian No. 9 played against South Africa on Sunday morning.

Now the French connection is joining the party, with Nic White posting a photo on Instagram with Mogg and Jake White flanked by Montpellier teammates.

South Africa's Pierre Spies and Fiji's Nemani Nadolo were among the big names at Montpellier to also shave their heads and send the photo to Lealiifano.

"Supporting a man down but not out @christianlealiifano you're in our thoughts bro #Buzz4Bruz #StayStrong," White put on Instagram.

Lealiifano will spend at least a month in hospital after being diagnosed following blood tests and feeling unwell at Brumbies training.