Sam Kerr has undergone knee surgery in London to repair her ACL tear

Sam Kerr has undergone knee surgery in England and one detail has ruined the Olympic hopes of Aussies around the nation.

Matildas captain Sam Kerr has undergone knee surgery in England opting against the “bracing” treatment method which could have provided some prospect of an earlier than expected return from her knee injury.

Kerr ruptured her anterior cruciate ligament during a training camp with Chelsea last weekend in a hammer blow to her Olympic dream.

Her Chelsea coach Emma Hayes confirmed Kerr went under the knife on Thursday and that the “recovery begins today”

“She’s having surgery today. Gutted for her, gutted for the team,” Hayes, who is leaving at the end of the season to take the reins of the US national team, told Sky Sports.

“These injuries happen in football, Sam knows that. I think the important thing is we are here to support her.

“The recovery, the rehab begins today.

“Today’s about letting her know she’s with her Chelsea family and we’ll look after her.”

Hayes said Kerr suffered the injury doing simple drills during Chelsea’s warm-weather training in Morocco and initially thought the injury was not that bad.

“Doing a football action she does every day - turning and shooting. Something every simple and innocuous,” she shrugged.

“Sometimes, we have a confirmation bias around ACL injuries, but they happen in the sport regardless of why they happen.”

Sam Kerr has had knee surgery after her ACL tear. (Photo by James Worsfold/Getty Images)

Kerr will miss Australia’s Olympic qualifiers in February and now the Paris Games.

She is also out of contract at Chelsea, where she was on track to sign a $1 million a year deal but Hayes said the 30-year-old only had one focus now.

“The focus for Sam right now is on rehab,” she said.

“I’m sure when the time is right to discuss her future, that will come from Sam and the club - but Sam loves Chelsea and Chelsea loves Sam, so I think that’s the most important thing to say on that front.”

Before opting for surgery physiotherapist and injury analyst Brian Seeney said the “highest chance” of Kerr playing at the Olympics would be to attempt a “bracing” recovery.

However, he said a “lot of things would have to be right” and that if the bracing didn’t work. Kerr would facing a longer period on the sidelines.

“It would have to be a clean ACL injury, with minimal secondary damage,” Seeney said.

“If you put the knee in a brace for about 10 to 12 weeks, there’s some evidence that the ACL in the right circumstances can actually heal on its own.

“Then you go through your rehab, and we’ve seen athletes come back at around that four-to-five month mark, or up to six months … but there’s not a lot of solid evidence, particularly at the professional sport level.

“It would be hard for someone like Sam Kerr to take such a risk when they don’t know the percentage outcomes of what’s likely to happen, but she could potentially be the first.”