Rising Melbourne Rebels backrower Sean McMahon looks poised for a Test call-up against Wales after seizing an unexpected opportunity against the Barbarians. McMahon came off the bench just 19 minutes into Saturday's 40-36 win at Twickenham, after veteran Scott Higginbotham was forced off with a hamstring injury.

And the 20-year-old made the most of his chance, producing a series of barnstorming runs, scoring a try and defending strongly to be one of Australia's best players. It's already been a dream year for McMahon, who won three awards at last month's John Eales' Medal awards night, but it appears likely to get even better.

With Higginbotham to miss the Test against Wales in Cardiff on Saturday, and possibly the rest of the tour, coach Michael Cheika indicated it would be hard to leave the Australian under 20s captain out.

"I thought he was outstanding," Cheika said of McMahon. "At the John Eales Medal the other night he was doing his fitness work by going back up to the podium to collect awards. "He got on the field and took his opportunity with both hands. With the injury to Scott Higginbotham there's a place in the backrow open for the Test next week and he's definitely put himself right up there."

Cheika said Matt Hodgson had also enhanced his selection prospects with a strong captain's knock against the Barbarians as he stood in for rested skipper Michael Hooper. Hodgson welcomed the competition for places.

"It's great. I think the depth in the backrow is strong and it's great for someone to step up on that stage and themselves against a quality side. He [McMahon] did great," Hodgson said.

Cheika said 31-Test veteran Higginbotham would be assessed in the coming days but suggested his tour may be over. "We'll wait and see the severity of it and then decide whether he stays or goes," the coach said.

Meanwhile, Cheika was pleased with the contribution of halves Quade Cooper and Will Genia, who returned to the Australian side for the first time this year. Cooper will be trying to oust incumbent five-eighth Bernard Foley in the coming weeks while Genia starts the tour as third-string half-back behind Nick Phipps and Nic White.

"I thought they did quite well and we must remember with those two lads they haven't played a lot of football," Cheika said. "There was a lot of football in that game, there wasn't many stoppages, so I thought they managed the game pretty well."

Sean McMahon was impressive on his debut and has made a strong push for a Test call-up © Getty Images

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