It is a measure of Jim McGrath's competence that the retirement of revered commentator Sir Peter O'Sullevan was not a forlorn one for BBC racing.

A racecaller of broad experience, McGrath's is the Antipodean drawl heard whenever Grandstand crosses to the galloping drama that is the sport of kings.

But for different circumstances almost 30 years ago, McGrath might never have made it to Britain.

Indeed, the incumbent voice of racing on BBC TV might have been a mimicry of the relaxed, balanced tones of O'Sullevan rather than those of McGrath.

Ambition drove a young McGrath out of his homeland in the early '70s, a lack of opportunities forcing him to pack his microphone and set sail for the racecourses of the world.

"I was calling in Melbourne and there were three excellent callers who had been there for at total of 100 years between them," McGrath tells BBC Sport Online.

"So I set off in 1973 and came here in 1984 after commentating in Hong Kong, essentially to work for Phoenix Park in Dublin doing course commentaries in the summer.

"I then got the opportunity to call a couple of races at York during the Ebor meeting in 1984.

"I got very favourable publicity in the racing press and also in the national press, and being a different voice and style attracted attention."

And so began his journey to the top of the racecalling tree.

McGrath soon joined the BBC under the wings of O'Sullevan and succeeded the celebrated commentator following his retirement in 1997.

But if he yearns for recognition in Australia (where he is little-known) as one of its finest media exports, it doesn't show.

"I don't really think you can structure your professional life to prove to those who are sitting in judgment that you're this or you're that," McGrath argues.

"I certainly wouldn't change my career direction to prove a point.

"I go back to do the Melbourne Cup every year and for me that's my little piece of indulging myself in the Australian racing scene. It's fantastic and I love it."

When McGrath speaks of his self-imposed exile from Australia, listen hard and you can hear the ambitious, yet ultimately disheartened, young man just trying to get an even break.

But he holds no regrets. In fact, things could scarcely have worked out better.

McGrath's yearly pilgrimage to call the Melbourne Cup for BBC Five Live represents more than a mere homecoming.

It's a culmination of his professional efforts, an affirmation of sorts. Nobody in Australia would be listening, but ask McGrath and he'd say nobody needs to.

In the grand scheme it's just another point of evidence that McGrath's career has come full circle.

By making it in the United Kingdom, McGrath's horizons have broadened immeasurably, his portfolio strong enough to make the most decorated racecallers down under weak with envy.

"I consider the BBC job to be the number one commentating job in the world because you've got such a great group of races to call," he states.

"But a lot of these jobs depend on how the incumbent develops it, and Sir Peter O'Sullevan developed it into a very important position.