The former coach of Nick D'Arcy expects the controversial swimmer to retire following his disappointing performance at the London Games.
D'Arcy failed to make the final of the 200m butterfly this morning, ending his Olympics campaign.
He finished sixth in his semi-final on Day Three in a disappointing time of 1:56.07.
His coach of 17 years, Brian Stehr, said he does not expect D'Arcy to continue his career.
"I'm disappointed for Nick because I would suggest that's the end of his career now," Stehr told ABC Local Radio.
"He just didn't look sharp. He didn't look as if he was ready to race in the Olympics at all.
"I'd be very surprised if he continues to swim."
D'Arcy had swam the third fastest time of the year when he won the Australian title in March with a time of 1.54.71.
But the 25-year-old was gutted he could not produce a similar swim in the Olympic semi-final.
"I'm pretty disappointed," D'Arcy said.
"I'm close to two seconds outside my personal best time. It was a tough swim.
"I just didn't have it in the last 100m. Everything needs to come together to make an Olympic final and it didn't tonight."
Japan's Takeshi Matsuda won the race in 1:54.25 and qualified fastest, while two-time Olympic champion Michael Phelps won the other semi-final and was fourth fastest.
Aussie Chris Wright, a 100m specialist, was eighth in the same semi-final as Matsuda and D'Arcy.
D'Arcy made the Australian Olympic team to London despite being excluded from the 2008 team following his assault of fellow swimmer Simon Cowley.
He qualified with his strong win in the Australian 200m butterfly title.
In the lead-up to the Olympics he was again embroiled in controversy when he appeared in a Facebook photo carrying high-powered guns alongside Australian team-mate Kenrick Monk.
D'Arcy is now due to head home from London as the Australian Olympic Committee (AOC) banned him from taking part in the closing ceremony or any other additional Olympic activities as part of a sanction for the guns photo.
Monk was given the same sanction by the AOC. His swimming commitments conclude tomorrow with the 4x200m freestyle relay.
Despite the AOC order to leave immediately after their Olympic events, D'Arcy and Monk have been reported to be flying home on August 4 at the conclusion of the swimming program.