The Wallabies flew out for their 2024 tour under a shadow. Australia had lost their past three Tests and five of their past six internationals, running last in the Rugby Championship and losing the Bledisloe Cup for a 23rd consecutive year. But the longest shadow was cast by one of their forebears: the 1984 Wallabies.

This most storied of sides were the first – and remain the only – Australians to win a grand slam, beating England, Scotland, Wales and Ireland. It was a monumental achievement that put the Wallabies on top of the rugby world for the first time. A Bledisloe Cup victory followed in 1986, a World Cup triumph in 1991.

“The side of 91 was exceptional but 84 captivated the nation – and the whole world,” says Simon Poidevin, flanker in the grand slam-winning squad. “To this day I get people all over Europe saying ‘thank you for 84’. It was a great example of Australian character: fit, tough, cavalier, with an awesome defensive record – just one try scored against us in four Tests.”

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It isn’t just Australian rugby fans and pundits who rate the 1984 Wallabies so highly; opponents on that tour remain in awe. “They were a great side, decades ahead of their time,” says England’s Gareth Chilcott. “That 84 side would’ve won the World Cup no matter who they played and no matter what the conditions,” adds Wales’ Eddie Butler.

Poidevin, who played all four Tests on tour, says the driving force was “vengeance”. “When we went away for the 81-82 grand slam, it was with very high expectations,” he says. “We had the Ella boys and a host of stars: Tony Shaw, Mark Loane, Mick O’Connor. But we flew into the worst English winter in 46 years and were in it for three months.”

Despite scoring eight tries to three across all matches, Australia won only a sole Test, against Ireland.

Bob Dwyer soon replaced Bob Templeton as coach but by 1984 a new man had taken the reins: Alan Jones. He was a junior tennis champion, opera lover and political speech writer who had earlier that year coached Manly to the Sydney premiership over Randwick.

“Alan was … interesting,” the fly-half Mark Ella says with a chuckle. “He knew we’d underachieved in the past and he was determined to succeed in 84. Alan doesn’t like to fail. He made us work our backsides off. It was win at all costs. I had a different perspective so we didn’t see eye to eye then, and we never did after.”

One of Jones’s first political plays was to replace Ella with Andrew Slack as captain. “I was shocked,” Slack says. “Mark was the first Indigenous man to captain [the Wallabies] and had done a really good job. But I was 29. Responsibility didn’t faze me. I’m good with people … and I lead a good singalong on the guitar.”

Poidevin still backs the coach’s call. “Slacky as skipper was the best selection Jones made on that tour,” he says. “He was down to earth, laid-back, and had a strong moral compass. And when there were blow-ups between the players and Jones, which were common, he defused it.”

“Alan was a motivator, a great rugby brain … but he stood on toes,” Slack says with a laugh.

That was apparent the moment the squad arrived at Heathrow on 10 October. “We had flown economy class the whole way, and for big men that’s a bloody long trip,” says Poidevin. “We got to the hotel and Alan barked, ‘Get yourselves ready – we’re training in an hour.’”

Led by Ella, an electric Wallabies side thrashed England 19-3 in the first Test despite fielding a new-look backline of the debutant half Nick Farr-Jones and the rookie No 12 Michael Lynagh. “I told Alan before the tour, ‘If we’re going to win games you’ve got to let me control the team,’” Ella says. “To Alan’s credit – and my surprise – he agreed.”

Ella notched the first try of the Test with “Leaguie”, a loop move he had honed with his Wallaby brothers, Glen and Gary, at Matraville High School. Poidevin scored the second. “I was like a sheepdog trailing Mark and ‘Campo’ [the winger David Campese] everywhere. Campo made space, Mark’s soft hands put me into a gap. A try at Twickenham!”

Australia next beat Ireland 16-9 in Dublin. Donal Lenihan, second-rower for the home side that day, recalls: “They had a level of skill that was just ahead of our people.” Those skills had been carefully, sometimes brutally, honed in fiery training sessions designed by Jones and run with the steely tactical acumen of the assistant, Alec Evans.

There were many unsung heroes – the bon vivant manager “Chilla” Wilson, father-confessor-medical officer Syd Sugarman, the scrum machine fans lugged all over Britain. But none more vital than “The Green Machine”, the “team within a team” of bench players whose war cry of “Many voices, one spirit” united the 36 tourists as a family.

“Without the Green Machine there’s no way the Test men could have survived such an arduous tour,” says Ella. “They made us one team, not a Test XV and the rest.”

Poidevin agrees: “Alan was masterful at managing tension between players vying for a Test spot. So we’d kill each other at training then get on the soup together afterward. We were mates toughening each other up for the real enemy.”

That was Wales, the world’s most famous scrummagers. “But our tight five was powerful too,” says Poidevin. “Topo Rodriguez was a scrum technician, hooker Tom Lawton was mobile, Andy McIntyre was a rock. Alan fixed our weakness, the lineout, with giraffes: a leaper Steve Cutler and lifters Steve Williams and Steve Tuynman.”

The Wallabies demolished Wales 28-9 in Cardiff, humiliating their legendary scrum with a pushover try in the 63rd minute. Suddenly a grand slam was one Test away. Ella had scored a try in every Test. “Everyone was talking about four in four games. As we ran out, [full-back] Roger Gould said: ‘Don’t worry ‘Mella’ I’ll take care of you’. And he did.”

Ella led Australia to a 37-12 win over Scotland. “The Wallabies’ rugby transcended patriotism,” wrote The Scotsman, “and left anyone with a real feeling for the game enchanted.” The grand slam was a landmark for Australian rugby. The Wallabies had won, and won playing brilliant, adventurous rugby. They would never be taken lightly again.

“Back at the hotel, we tried to comprehend what we’d done,” says Poidevin. “Slacky stood up and spoke about each player. Topo [Rodriguez] began to cry. Then everyone started to cry. Joy, relief … we’d done it.” That night the credo “If you can’t show up, don’t play up” was shelved. “We poured Alan four fat knuckles of Scotch – and he nailed it!”

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For Ella and Slack the night was doubly emotional. Both retired after the tour ended. “We knew winning a grand slam was huge for the game,” says Ella. “But my mind was made up. Yeah, I was only 25 but my plan had always been to retire. I came home and four days later I married my wife. One chapter ended, another began.”

Slack went back to life as a school teacher and later ran Channel Nine Queensland. “Even now the magnitude of what we did makes me well up with tears,” he half-sobs. “I don’t really remember the Tests, only the people. We did it for our families, for the game in Australia, for ourselves. But first and foremost we did it for our teammates.”

• This article was amended on 11 November 2024 to reflect that Mark Ella was the first Indigenous Australian to captain the Wallabies.