Australia and Western Force hooker Brendan Cannon has been forced to retire from the sport because of a serious neck injury.
Cannon's final Test was against Italy in November last year
The 34-year-old sustained his second serious neck injury in a year while playing for Western Force against Canterbury earlier this month.
"I really didn't have any option," said Cannon, who won 42 caps for Australia.
"As much as I wanted to play on, I really couldn't. It would have been very silly for me to tempt fate again."
Cannon was carried off the pitch on a stretcher after a scrum collapsed in the match against the Crusaders on 7 April, almost exactly a year after a similar injury sustained against the same opponents.
"I feel very privileged to have competed at the elite level for so many years, and to have met and played with so many wonderful people," added Cannon.
"I never really expected to play one Super 14 game of rugby, never mind 100, and the honour of wearing the Wallabies jersey will always stay with me.
"I didn't want to jeopardise my future as a good husband and father, so the decision was really driven by my commitment to my family."
Cannon, who made his Test debut against the Lions in 2001, also played for New South Wales and Queensland.
The announcement of Cannon's retirement comes two days after that of 28-year-old England hooker Steve Thompson, who also sustained a serious neck injury.
The pair packed against each other in the 2003 World Cup final, which England won 20-17.
Last week, Cannon criticised rugby union's new scrum engagement laws, for making scrummaging more dangerous.
The new laws require the two packs to go through a four-stage "crouch, touch, pause, engage" process.
"In some ways it has probably brought an element of danger to it because the front row have to be balanced there for a longer period of time, and you have anywhere between 900-1,000 kg behind you," he said.
"You may not get many guys that want to speak out publicly about it, but I think there is a general frustration there."