The giant No 12 managed to lift the Webb Ellis trophy four years ago without breaking anything but since then he has become a one-man hospital ward.
As a result, the former league star has played a mere 37 games of XVs rugby since the glorious Twickenham final, partly because of his ill-fated sevens switch in 2016.
This XVs total includes 18 tests, 18 Super Rugby games for the Blues, and one match - his last - involving 50-odd minutes for Ponsonby more than three weeks ago.
It's a dreadful return for New Zealand Rugby, who had to dig deep into the war chest to keep him from overseas offers.
Reliable reports about the size of his contract are hard to find. But his three-year deal would probably crack the $2m mark.
Familiar sight...Sonny Bill Williams getting medical attention. Photo / Photosport
And even his rare appearances since 2015 have been filled with problems including an Olympics disaster.
Williams became the first All Black to be sent off for half a century, a costly moment during the 2017 series against the British and Irish Lions. He has been yellow-carded twice and regularly replaced during tests in that time.
He lasted just half an hour before a shoulder injury forced him off in his last test against England about eight months ago. And four of his rare Super Rugby appearances since 2016 have been off the bench.
It says something for his mana and ability that Williams' stocks with the All Black selectors remained strong as he notched up the equivalent of two sabbaticals without leaving home. But how long will that faith last?
As for comparisons with other players ... it doesn't make pretty reading for SBW fans.
Since the 2015 World Cup final, iron man lock Sam Whitelock has amassed 91 games in the All Blacks and Crusaders engine room.
One of SBW's rivals for a test midfield spot, a battered Ryan Crotty, has notched 86 games despite his constant injury problems.
And for an NRL comparison, the remarkable Melbourne Storm skipper Cameron Smith - who is older than SBW - played 32 games in 2017 alone during the World Cup, State of Origin and NRL.
It all started going wrong for SBW in 2016 when he suffered a horror Achilles injury in the first game of the Olympic sevens tournament.
There was a bad omen as his ambulance driver got lost in Rio, and since then he's dealt with shoulder, wrist and knee injuries, and even managed to pull a hamstring at an All Blacks camp.
Not that his breathless suitors are bothered. A Canadian league team and his old Bulldogs NRL club are among those reportedly interested in signing SBW, who turns 34 next week.
Saturday night shapes as a massive moment in the career of a New Zealand sporting icon - any more injury problems and his World Cup hopes could be over.
