"My wife phoned family and friends and said, 'Listen, I think he is on his way out'," Burger told the Daily Mail last month. "I didn't open my eyes for five days. I was there but sometimes it felt like I was going to stop fighting and then I would go, I'd be gone. Every heartbeat it felt like someone was putting a knife straight into my head."
The problems started for Burger in early 2013 when he found a lump in his left leg. A scan found a cyst in his back which was depressing his spinal cord. After an operation to drain the cyst, infection set in, which contaminated his spinal fluid.
"This was the scary part," the 32-year-old father-of-two said. "I went in weighing 110kg and things just changed like that. I had my first operation and then I was in dire straits - I knew I was in trouble.
"It was more scary for everyone around. I was battling heartbeat by heartbeat just trying to get through and that lasted for five days. I had another four operations to get rid of the cyst and pressure on my spinal cord and came out of hospital weighing 90kg."
The blond flanker - who has good friends among the All Blacks, including fellow loose forwards Jerome Kaino and Kieran Read - had to teach himself to walk again, but last year was recalled to the Springboks and quickly found the destructive form which has made him one of the most feared flankers in world rugby.
The 84-test veteran credits his laid-back attitude towards rugby in part to his illness, saying it helped put his life in perspective.
"The great thing about Schalk is that I still can't work him out. He's an amazing human being," Meyer said. "If you just check what he's been through, for him just to be alive is great, that's why he just enjoys life.
"I'm a little bit more uptight at times and Fourie [du Preez], the captain, is as well, but Schalk is more relaxed and I think you need that balance.
"He's always dying for a joke. Even before we go into battle he's still fully smiling and I think he's not ready and then when he goes on the field he's a different human being. You need that, you need characters in the team and he's one of them."
McCaw, 34, and with 146 test caps, is more clinical in his approach to the game than the passionate Burger, but that ruthless efficiency allows him to respond to pressure and makes him so important to the All Blacks.
"He's become one of the great leaders of world rugby, especially under pressure," coach Steve Hansen said. "He's well-supported by Kieran [Read] and the rest of the leadership group. There's a lot of mental fortitude there. We've been through some tough times and had success in those tough times and that breeds I guess a deep-seated self-belief."
Dan Carter, who has played alongside McCaw for many years with the All Blacks and Crusaders, said: "He's a fantastic player both on and off the field. He's a real inspiration and a player who really motivates this side, first of all because of his actions. At training he's always first out there and last to leave. His work ethic is fantastic. Also, out on the field he's the first guy to put his body on the line.
"When you're working so closely with him that inspires you to do the same ... I feel pretty honoured to play alongside such a legend."
McCaw has shown time and again his ability to bounce back from the heaviest of knocks - both legal and illegal - from his opponents. Burger has shown the ability to come back from those too, plus an illness that nearly left him dead.
McCaw v Burger - a heavyweight contest on every level.
1-NZ v 5-South Africa
Twickenham, 4am tomorrow
Head to head
Played 90, New Zealand won 52, South Africa won 35, drawn 3
World Cup meetings
1995 final: South Africa won 15-12, Johannesburg
1999 third place playoff: South Africa won 22-18, Cardiff
2003 quarter-final: New Zealand won 29-9, Melbourne
Last five meetings
2015: New Zealand won 27-20, Johannesburg
2014: South Africa won 27-25, Johannesburg
2014: New Zealand won 14-10, Wellington
2013: New Zealand won 38-27, Johannesburg
2013: New Zealand won 29-15, Auckland
NZ's path to semifinal
Pool games: bt Argentina 26-16, bt Namibia 58-14, bt George 43-10, bt Tonga 47-9
Quarter-final: bt France 63-12
South Africa's path to semifinal
Pool games: lost to Japan 32-24, bt Samoa 46-6, bt Scotland 34-16, bt USA 64-0
Quarter-final: bt Wales 23-19