The Wallabies will be without veteran scrum-half Jake Gordon for the entire Test season, the halfback confirmed to have ruptured his Achilles in the Waratahs' season-ending loss to the Force on Saturday night.
The Waratahs on Monday revealed Gordon had undergone successful surgery and would soon begin his road to recovery, which will likely have him sidelined until 2027.
Gordon was making his return from illness in Perth having sat out the Waratahs' win over the Drua and loss to the Brumbies, only for his Achilles to give way as he set off from a quick tap just before halftime.
The Wallabies halfback joins lock Will Skelton, who also ruptured his Achilles, on Australia's long-term injury list, as coach Joe Schmidt prepares to name his squad for the Nations Championship.
Gordon's injury may however have spared Schmidt a difficult decision at No. 9 with Brumbies halfback Ryan Lonergan arguably the standout Australian player in Super Rugby Pacific this season.
With Tate McDermott having finally returned from a long-term hamstring injury, the trio all would have had claims to the No. 9 jersey for the first Test with Ireland, but Gordon's injury could see Lonergan earn his first run-on Test start with McDermott used in his super-sub role off the bench.
Meanwhile, Reds centre Hunter Paisami could also yet be a scratching for July after he suffered an injury in Queensland's win over the Drua on Friday night.
Paisami will miss the Reds' qualifying final clash with the Chiefs on Saturday, with Isaac Henry, Filipo Daugunu and Dre Pakeho all options to partner the in-form Josh Flook in the midfield in Hamilton.
The good news for Schmidt is that Exeter's Len Ikitau is well advanced in his return from a shoulder injury that sidelined him earlier in the year, while Australian rugby's highest paid player Joseph-Aukuso Suaalii produced his best performance of the season in the Waratahs' six-point defeat by the Force.
Suaalii made one tackle-shredding run from a lineout set play in the second half in Perth, and genuinely looked threatening every time he touched the ball.
The code-hopper has however been outshone by Queenslander Flook, who has excelled for the Reds in the No. 13 jersey this season. The midfielder is off to Benneton in Italy at the end of the season on a two-year deal, but so good has his form been that Schmidt may yet include him for the July campaign against Ireland, France and Italy.
Flook would then certainly be in contention under Les Kiss, who will replace Schmidt as Wallabies coach from August, the Queenslander's first assignment a two-Test series against Eddie Jones' Japan.
Elsewhere, Wallabies prop Angus Bell's stint with Ulster has officially come to an end after the Irish province failed to reach the United Rugby Championship playoffs. Bell had before that made a successful return from a foot injury and started at loosehead prop in Ulster's European Challenge Cup final defeat by Montpellier.
Ikitau's return from England will be determined by Exeter's Premiership clash with Saracens this weekend, so that that of teammate Tom Hooper, with the winner to advance to next week's semifinals. Versatile forward Hooper is expected to make Schmidt's squad as one of three overseas-based players despite him having another year, at least, to run on his Exeter contract.
Hooper has become a fan favourite in south-west England, while his ability to cover both lock and the back-row make him a valuable asset at Test level.
Schimdt is expected to name a Wallabies squad of around 36 players towards the middle of the month, with players from the Waratahs and Perth to join a train-on squad in Sydney from next week.