Joe Schmidt has only made one change to Australia’s starting XV before this weekend’s Test against England, but it is a big one. Joseph-Aukuso Suaalii, 21 years old and 6ft 5in, has been picked to start his first ever game of professional rugby union. Suaalii has not played the code since he was a schoolkid, but, with only four Tests left on this tour before Australia’s first against the British & Irish Lions next year, Schmidt is running short of time to find out if Suaalii is up to international rugby union after his A$5m (£2.54m) switch from rugby league.

Schmidt admits it is a risk. “Everything is,” he said. “The thing that gives me confidence is how well Joseph prepares himself. He’s a very professional young man. He’s had plenty of experience both playing rugby union, and as a professional in rugby league. So hopefully he can hit the ground running.”

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Schmidt’s not the gambling sort. He refused to pick either Will Skelton or Samu Kerevi for this Test because he did not think they were ready yet after joining up with the squad at the beginning of this week.

But he does not seem to have had a lot of choice about Suaalii, especially because Hunter Paisami, who played centre against New Zealand in Australia’s last Test, is out injured. “I guess for us, there’s four Test matches left this year before we embark on a massive Lions tour next year. So if not now, when? It’s unlikely it’ll go perfectly, but it will be a benchmark that he can build from.” He will be alongside Len Ikitau, and up against England’s experienced centre pairing of Ollie Lawrence and Henry Slade, who are playing in their eighth consecutive Test together.

“Slade has obviously got a lot of experience, but that’s one of the challenges. In four Test matches’ time, Slade may well be in the British & Irish Lions, or if it’s not him, it’ll be another highly capable athlete like him.” Schmidt concedes that he’s had one eye on 2025 all year. Suaalii is the 18th debutant he has picked so far, but he is the only one who has got the sort of crossover appeal that can draw the attention of the Australian public. “We don’t do press conferences about the team any more, we do them about Joseph,” Schmidt said, only half joking.

Suaalii has got big shoulders, but it is a hell of a lot of pressure to carry. “We try to protect him from that. But he’s a really level-headed kid, and so that gives us some confidence that he will cope,” Schmidt said. “He is a very humble young man, but he is very forthright about his preparation, and that gives us confidence. He played through the age grades. He played a lot of rugby in school, played through the pathway of Australian Under-18s, and he knows a number of the players through those teams as well.”

None of which means he is ready for this. But, Schmidt says, “we’ve got to find out some time. You know, if not this week, as I said, it’s next week or the week after that. No matter what Test you play up here, it’s going to be really competitive, combative and a benchmark experience for the young man.” He is not the only one; 14 of Australia’s 23 are playing their first game at Twickenham. Only one of the starting XV has played more than 50 Tests, prop Taniela Tupou, although the two veteran forwards James Slipper and Allan Alaalatoa are both on the bench.