Former Australian 800m record holder Joseph Deng has been forced to withdraw from the Birmingham Commonwealth Games team due to an Achilles tendon injury.
It is the same injury that ruled the 24-year-old Deng out of the world championships in Eugene.
Australian team medical officials wanted to give Deng an injection to bring down the inflammation in his Achilles, but that would need to have been administered more than five days before the start of competition and they ran out of time.
"Everything was going really well," Deng's coach Justin Rinaldi told AAP.
"Joe had a little bit of a quad niggle before he ran the 1:44 (in France in early July) and we backed off training.
"I think because he was trying to protect that quad it hurt the Achilles on the other leg.
"It's a bit of bad luck because he was coming in off a short build-up, he didn't have a massive base.
"We had to take some risks and it was probably a bit much too soon."
Deng set the national record of 1 minute 44.21 seconds in 2018, a time that stood for three years until it was bettered by his training partner Peter Bol at last year's Tokyo Olympics.
Athletics Australia (AA) are hoping to bring in Jye Perrott as a like-for-like 800m replacement for Deng in the Commonwealth Games squad but it seems like a long shot.
AA and James Templeton, who manages Perrott, Deng and Bol, have made representations to Commonwealth Games Australia on Perrott's behalf.
The 23-year-old clocked a PB of 1:45.61 in Germany in June.
Australia's other entrants in the men's 800m for the Birmingham Commonwealth Games, which begin next week, are Bol and Charlie Hunter.