Wallaby admits to injecting painkillers
The 27-year-old, who joined English Premiership side Sale Sharks last year from top French club Toulon, made the startling admission on his Instagram account.
O'Connor said he injured his ankle before the start of the 2016 season at Toulon and self-medicated so he could play through the pain barrier.
"On the 3rd day of preseason in 2016, I injured my ankle at Toulon," said the softly-spoken O'Connor, who has played just 13 times for Sale this term.
"Since then I've been fighting to play for nearly 2 seasons!
"It got to the point where I was only training 1 session a week and injecting it with local anaesthetic just to be able to take the field."
He said he was motivated by Toulon's bid to win the French championship, which ended in defeat to Clermont in a pulsating final last June.
"I was so determined to play and win a final with Toulon that I disregarded all the signs and carelessly played on," he said.
O'Connor, who left Toulon under a cloud following a cocaine bust, disclosed that he had reconstruction surgery on the joint before arriving at Sale for the start of the 2017 season.
However, the problem persisted for the back seen at one point as the future superstar of the Wallaby team, earning 44 caps by the age of 23 before various scrapes resulted in him losing his contract with the Australian Rugby Union.
O'Connor insists that he played with the injured ankle, not because of pressure from Toulon or Sale but because he was so desperate to succeed on the pitch.
"I did whatever I could to get onto the field to play… 3 games on, 2 weeks off and cortisol to Platelet-rich plasma [PRP] injections became my routine!" he wrote.
"This pressure in no way came from the club. I thought I could beat this through force & never actually allowed myself to stop and heal correctly."
As a result, O'Connor says he is back to where he was last year – facing more surgery on the injured joint.
Only this time, he says, his club have taken charge of his treatment.
"So now I’m here in the exact same place I was last year, 1 surgery down with another to go," he wrote.
"But this time around we [club & I] have taken all the correct measures and discussions with my surgeon, going over all possibilities and put together a great rehab program to get me back for next season faster, stronger and pain-free!"