It involves the 2008 Melbourne Cup which was a landmark day for steward Terry Bailey. Apart from the fact that he was chairing his first Cup, the afternoon and early evening was hectic. Stewards were run off their feet putting out spot fires.

After arriving in Australia to much publicity, the Irish-born O'Brien had brought to Australia three stayers to compete in the Melbourne Cup. His appearance in Melbourne sparked much discussion and excitement.

Johnny Murtagh was riding Septimus, Colm O'Donoghue was on Honolulu and Wayne Lordan on Alessandro Volta  all established a huge lead in the early stages of the race and, by the top of the straight, they all compounded to finish near the rear of the field.

Punters here and overseas were screaming about the riding tactics of O'Brien's trio.

On Monday, Bailey said it was natural that all three jockeys be asked to give evidence.

"They know that's how it's done. It doesn't matter if it's at Swan Hill, Mildura or Flemington, questions had to be answered " Bailey said.

"They (jockeys) all had different stories so we had to get to the bottom of it. What would punters who backed Septimus think if I just went ahead and not bothered looking into it," he said.

The chief steward contacted O'Brien, who had   issued the original instructions to jockeys, and called him back to Flemington.

"I think he was at the casino packing to go back home to Ireland but the matter had to be dealt with now because the jockeys were travelling in different directions and so was the trainer," Bailey said.

He and his panel considered charging one of the jockeys with failing to allow their mounts to run on their merits but that was thwarted when veterinary advice showed that two of the three stayers had pulled up sore and the third "was in a bad way".

Nearly 90 minutes after the last race O'Brien returned to Flemington and admitted that he didn't get the tactics right but had considered scratching the horses "because the ground was like concrete".

O'Brien challenged Bailey to take action, saying: "if you are going to penalise me or the lads, that's a nonsense, we have come here in good faith".

However Bailey retorted that "the question we asked of your riders is what we do every day and we got conflicting answers. It is a natural to ask the trainer to clarify the evidence - whether it's Aidan O'Brien or a one-horse trainer from Colac".

O'Brien has never returned to Australia.  Some maintain it's because of a smouldering dislike for Bailey.

However, the chief stipe sees it another way.

"There's no bad blood. We (stewards) sit around the table and ask hundreds and hundreds of questions every day a race meeting is staged. We had three horses from one stable charge out in front. And one of them had been seriously supported so I make no apology for the questions I asked."

Six years on, O'Brien's stamp on this year's spring carnival returns with the northern hemisphere-bred Adelaide in the Cox Plate. After the race, Adelaide will be sent to trainer Chris Waller.

O'Brien won't be at Moonee Valley but, according to Bailey, it wouldn't matter if the world's leading trainer did appear trackside on Saturday.

"What we did in 2008 is what we do every day. Ask a lot of questions and make sure everybody understands that we are only doing our job."