McMahon made a return to his ‘Mad Dog’ moniker in Dunedin on Saturday, leading the Wallabies in carries and making 11 tackles, among the best of his 16 career Tests.
The display made fans wonder why the 23-year-old is on the verge of leaving Australia for two years, a span that will include the 2019 Rugby World Cup.
And punters weren’t alone.
Cheika wasted no time in talking up McMahon post-match and spontaneously making the 23-year-old’s, still yet to be announced, Japanese club very nervous.
McMahon’s deal is an interesting case, not beginning until the 2018/19 Top League season, with the possibility that he could play both in Japan and Australia in a World Cup year, pending approval from his Japanese club and also his ability to find a Super Rugby home ahead of the tournament.
The Queensland-born back-row has until now, though, said he’d all but closed the door on the possibility of a World Cup role in 2019.
“There’s a word for Sean McMahon tonight, that was outstanding,” said Cheika.
“He was truly outstanding, he just gave it everything.
“That’s the Sean McMahon we know and that’s why I’ll be aiming all guns towards Japan to try and get his contract torn up over there or something like that.
“I don’t care what it takes to make him stay here because we want him here.”
Asked whether he thought there was some prospect of McMahon reneging on his deal or making himself available for the World Cup, Cheika said he wasn’t sure.
“Nope, just made it up now,” he said.
“Maybe sometimes it’s nice to say publicly how badly we want a player to stay here.