Tom Clarkson's late try helped injury-hit Ireland kick-start their Nations Championship campaign with a thrilling 33-31 victory over Australia in Sydney.

After New Zealand edged France 34-32 in the first-ever match of the new 12-team competition, another clash between two heavyweights lived up to expectations in an enticing 10-try contest on Saturday.

Rocked by the late news of Robert Baloucoune's absence, Ireland – who were without 13 injured players – fell behind when Dylan Pietsch crossed untouched in the corner after just three minutes.

Cian Prendergast powered over in response before Josh van der Flier's try put Ireland ahead after Jock Campbell had grounded for Australia, with Carter Gordon missing both Wallabies conversions.

However, Australia led 24-19 at the interval after back-to-back converted tries for Josh Canham and Ryan Lonergan, with Jamison Gibson-Park racing under the posts on the stroke of half-time for Ireland.

Hugo Keenan carried that Irish impetus with another try in the second half, though Tate McDermott soon hit back to make it 31-26 to Australia, before Dan Sheehan's finish was ruled out on review for James Ryan disconnecting from the maul.

Lachlan Shaw's sin bin with four minutes remaining, punished for repeated infringements, flipped the match on its head as Clarkson bundled over and Sam Prendergast added the extras. 

Australia had a late chance to win it, but Ben Donaldson missed a last-gasp penalty when he opted to kick from far out on the touchline, as Ireland held on for a hard-fought victory over the Wallabies.

Hell of a Test W! pic.twitter.com/qOtzIrPbci

— Irish Rugby (@IrishRugby) July 4, 2026

Ireland put Europe on the map with more Wallabies success

The new-look competition has billed the European sides – those who compete at the Six Nations – against the rest of the world, and it is fair to say it had been a one-sided start.

New Zealand overcame France earlier in the day, while Japan claimed a 27-10 victory over Italy, thanks to Takuro Matsunaga's 17-point haul at Prince Chichibu Memorial Stadium.

But Ireland did not bow down to their southern hemisphere rivals, despite Andy Farrell's side being hit by numerous injury issues before and in the build-up to the start.

In holding on here, Ireland have now won their last six meetings with Australia, though Farrell may have one eye on a clash later down the line.

His side face Japan next Saturday in Newcastle before ending their July internationals with a trip to Eden Park, where New Zealand have not lost in 32 years (51 Tests, 49 wins, two draws).

Australia, meanwhile, will have to dust themselves down before hosting France in Brisbane.