He had been picked to play in the first State of Origin clash two days later.

Having already represented his state in two victories earlier in the 1980 season, the match appeared to be a bit of a novelty.

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For so long, the true honour had been to earn selection in the NSW team. With the sport's top players featuring in the Sydney competition, that was a sign you were among the game's elite.

But for this one match the teams were picked on place of birth.

It seemed a gimmick at the time. Those views quickly changed when Cronin ran on to Lang Park in front of 33,210 screaming Queenslanders.

"No one knew how it would be received," Cronin said. "NSW had dominated the interstate competition for the previous 20 years, it was dying. We had won the first two games, so this was a one-off game to try to revive it.

"We knew when Queensland trotted out that it was serious. We could tell from the crowd that they were fair dinkum and their response when Arthur Beetson came out, they came out fired up."

Forty years later, the game that started as a one-off event has turned into the sport's showpiece.

While at its heart State of Origin is a contest between NSW and Queensland, Wednesday night's clash at the Adelaide Oval showed the series transcends borders.

As Cronin realised on July 8 1980, the event has always held meaning to those living north of the Tweed.

It took some time, however, for the Blues to realise what Origin is all about.

"It was always more important for Queensland than NSW, it took a while for NSW to realise that," Cronin said.

"The first year NSW won the series, in 1985, that was the first year NSW put players in camp and realised they were falling behind.

"It took them a while to catch on, but the Blues have now. NSW have got a bit complacent at times, then Queensland gives them a jolt like we've seen recently."

Cronin's role in the first Origin clash has gone down in rugby league lore, the three-quarter hit high by fellow Parramatta star Beetson.

With club teammates refusing to hold back, the shot showed how much the players cared and was a sign the concept had legs.

Or so the story goes.

The Gerringong talent is quick to downplay the incident, instead pointing to a first-half melee involving Beetson and Graeme Wynn as crucial to setting the stage for 40 years of hatred.

"That's one of those stories that keeps on going," Cronin said. "What happened in that game would have easily happened at training. We travelled back on the plane together, it didn't affect our friendship.

"There was a brawl early in the game that helped prove the officials right. They wanted to make it into something and they've turned out right.

"Outside of the grand final, it's the biggest thing in the game. It's turned out a great success."