Cusack is a surprise inclusion on the Canberra Vikings bench for their round two National Rugby Championship match at Parramatta Stadium on Thursday night.

The 21-year-old helped the Australian sevens team win a bronze medal at the Commonwealth Games in Glasgow last month and hopes to be a part of the Olympic Games campaign in Rio in 2016.

But a year ago Cusack was on the verge of winning a contract with the ACT Brumbies before he ruptured his anterior cruciate ligament in a club game for Royals.

Australian sevens coaches had so much faith in him they picked him to play in Glasgow despite not having played in 12 months, and he repaid them with a medal.

Cusack has been released to play for the Vikings for the next month to get more game time and admits he still has a desire to play Super Rugby.

"You always have doubts when you injure your knee, but I've had 12 months and it's not really a problem," Cusack said.

"A taste at the Comm Games really excited me thinking about the Olympics, who knows what can happen.

"I've always had the ambition to play Super Rugby and will always have it. But the excitement of the Olympics keeps you in sevens. I'm still young and hopefully have a long career."

Cusack has a deal with the sevens team until the end of next year. He played in the Australian under-20s 15-a-side team before making the switch to sevens.

The former Marist College student will bolster the Vikings' line-up as they chase their first win of the inaugural NRC season.

He will start on the bench for the clash against the Greater Sydney Rams and will add much-needed punch to the Vikings after their disappointing start to the year.

Cusack is using his NRC stint to get more game time before the Gold Coast sevens in October.

Wallabies hopeful Christian Lealiifano will also get his chance to impress Test coach Ewen McKenzie in the hope of being recalled to the international arena.

"We know what Christian's capable of, he's the first to put his hand up and say he's not quite where he knows he can be," McKenzie said.

"I've had a couple of chats to him. He's a terrific contributor to the team, but he wants his football to do the talking.

"He's not far away and he's probably looking for opportunities to show where he's at. The little things will start turning for him."

NATIONAL RUGBY CHAMPIONSHIP ROUND 2

Thursday: Greater Sydney Rams v Canberra Vikings at Parramatta Stadium, 7.30pm. TV time: Live on Fox Sports 2.