Recalled Wallabies midfielder Berrick Barnes has promised to repay the selectors' leap of faith at next month's Rugby World Cup in New Zealand.
The 25-year-old's dream of attending rugby's showpiece event for the second time appeared all but over when he chose to take an indefinite break from the game in June.
Barnes suffered a series of head knocks early in the Super Rugby season and was diagnosed with the career-threatening 'footballers migraine' condition.
The former Wallabies vice-captain spent a month researching and trialling a variety of alternative treatments before making a strong return for club side Sydney University.
"It's a big relief," Barnes said of his inclusion in Australia's 30-man squad at Sydney airport on Thursday morning.
"I worked pretty hard to obviously have a shot at this opportunity so I'm pretty thankful that the selectors showed a bit of faith in me and that sort of thing, so I've got to repay it now I suppose."
The Waratahs playmaker edged out Matt Giteau for the role of Quade Cooper's understudy and is also a strong contender for the starting inside-centre job.
He is well aware he'll be targeted by opponents but says nothing they dish out can top what he's already endured in training.
"I've been doing a fair bit of work off the field in terms of training stuff to put myself in a worse position than what I've been doing on the field, so as long as I keep doing that I'm confident going out there, that's for sure," he said.
"No doubt they'll send cattle my way, but they send cattle at anyone that stands at 10 so I won't be surprised if they're coming down that channel at whoever's there."
"I'm confident going into games and I've just got to trust what I've done off the field is going to be enough to get me through on it ... mentally I feel 100 percent."
Barnes is expected to turn out for the Australian Barbarians against Canada on the Gold Coast next Friday.
Meanwhile, Waratahs winger Drew Mitchell expressed relief after earning selection despite not having played a game in four months.
Mitchell broke his ankle in a collision with Wallabies team-mate Scott Higginbotham in the Waratahs' loss to the Reds back in April.
He is a chance to make his return in the club ranks this weekend and will be considered for the Barbarians match next week.
"I feel obviously really excited and honoured as well," Mitchell enthused.
"It was never a clear thing whether I was going to make it back or not but I guess once I did the injury and we spoke to the surgeon the first time and he gave me a glimmer of hope, of course I was going to hold on to that."
"Then as my rehabilitation progressed it became a bit more obvious that I was going to be a bit more of a chance."
Asked if he has patched things up with Higginbotham, who appeared to alter his course to block Mitchell before the pair collided, Mitchell said: "We had a chat a long time ago about that (the injury) and there's certainly no hard feelings there or anything like that, we've had a bit of a laugh about it and we've moved on."