Australia's chances of gold on the track in Beijing have plummeted after world champion walker Nathan Deakes joined Jana Rawlinson on the casualty list on Monday.
Deakes withdrew from the Olympics due to a hamstring injury, Athletics Australia confirmed.
The 50km walk champion has battled chronic hamstring problems for the majority of the past four years.
He suffered a reoccurrence of the injury at his training base in St Moritz, Switzerland, last week. Scans revealed a tear that will require surgery for the Athens bronze medal winner.
"I'm still in a bit of shock," Deakes said.
"I'm sure it will sink in in the middle of August when I'm watching the Games."
He said the choice to pull out of the team for Beijing was not up to him.
"There was no decision to make unfortunately, my body made the decision for me."
"I have to have surgery to fix it as the hamstring tendon has come away from the bone at the pelvis. It will mean a six to nine month recovery process."
Deakes previously had surgery on the hamstring in 2003 but returned to win a bronze medal in the 20km event at 2004 Games.
The problem resurfaced in 2005 and forced his absence from the world championships.
Deakes bounced back to win the 20km and 50km gold medals at the 2006 Commonwealth Games, ahead of his world record performance in Geelong in December 2006 and victory win in Osaka.
Deakes has only raced once since his world championship triumph in Osaka last August.
Australia will be represented by Jared Tallent and Adam Rutter in the men's 50km walk on the morning of Friday, 22 August in Beijing.