He also placed 12th in the 100m backstroke and won a silver medal as a heat swimmer in Australia’s 4x100 mixed relay team.

Australian Commonwealth Games Association chief executive Craig Phillips said his body was short of detail on the matter but said he was confident SA would take care of the athlete’s wellbeing.

“We have received advice from Australian Swimming,but we don’t have the detail around that. We’re waiting on more details around it from Australian swimming,” Phillips said.

“Obviously,a difficult decision to take,and I know they certainly have some concerns for Isaac’s wellbeing.”

Birmingham chef de mission Petria Thomas,the former champion swimmer,wished Cooper well as he sought to come to terms with his issues.

“It’s obviously a challenging time for young Isaac and we wish him all the best back in Australia. I suppose it becomes a wellbeing matter.”

The Stilnox affair was a formative moment for Australian swimming after a poor Games in 2012,so it was little surprise this latest incident around medication evoked comparisons.

Eamon Sullivan,Matt Targett,James Magnussen,James Roberts,Tommaso D’Orsogna and Cameron McEvoy were sanctioned over the use of Stilnox at a bonding session. All but Roberts admitted abusing the sleeping medication,which had been banned by the Australian Olympic Committee.

The six swimmers were fined and given deferred suspensions by SA.

SA also announced that para-swimmer Tim Disken will miss the Games due to injury following recent surgery. Disken,a four-time Paralympic medallist,is the reigning Commonwealth champion in the 100m freestyle S9 and 100m breaststroke SB7 events.

With AAP

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