Dual Commonwealth Games gold medallist John Steffensen has threatened to sit out the London Olympics in protest if teenager Steve Solomon receives the only 400m spot.
The controversial runner took to Twitter to vent his disgust at Athletics Australia's (AA) decision to provisionally name the 19-year-old Solomon for the one-lap race.
AA said it had to name a runner for protocol purposes and that both Solomon and Steffensen remained in contention for the berth despite neither meeting the automatic qualifying time of 45.3 seconds.
Both had already been chosen for the 4x400m relay.
Solomon burst into contention for the individual run by posting a career-best 45.52s at the world junior championships in Barcelona this week.
Steffensen, who set his season's best time of 45.61s in February in Sydney, defeated Solomon at the Olympic trial in March before suffering a hamstring injury that has plagued his London preparations.
The Melbourne Commonwealth Games 400m champion said he had accepted that he was only deserving of a relay spot but took umbrage at Solomon taking the spot without an A qualifier to his name.
"I dnt want no handouts cause I didn't earn my spot!!," Steffensen wrote.
"But if they put another ath ahead of me then I'm pulling out the games!!"
He added: "I knew the rules!! And rules were an A and u run!! Now it's a B and u run if u are Steve Soloman!"
An AA spokesman said that Steffensen and Solomon had the chance to press their cases for selection in the coming weeks with Australia able to change the runner up until 24 hours before the August 4 heats.
Steffensen lashed out at AA for the manner in which they delivered the news to him.
"this is the respect I got!! No phone call just this cheap ass email!!," he said.
He all but accused AA of bias towards the younger runner.
"Let me make it clear Steve is the truth!! But we all knew the rules!! Tell me would they be pushing so hard for me if I had the B!!," he said.
Steffensen was a member of Australia's silver-medal winning 4x400m relay team at the 2004 Athens Olympics but has never been selected for an individual 400m berth at the Olympics.