The centre-back travels to Russia two and a half years after fracturing his kneecap on a sprinkler during his debut for Dutch side PEC Zwolle

This article is part of the Guardian’s 2018 World Cup Experts’ Network, a cooperation between some of the best media organisations from the 32 countries who have qualified for Russia. theguardian.com is running previews from two countries each day in the run-up to the tournament kicking off on 14 June.

At the start of 2014 Trent Sainsbury had the world at his feet. After emerging in the A-League with Central Coast Mariners and winning his first trophy in the grand final, he secured a high-profile transfer to Europe. At 22, he was one of Australia’s best young players.

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A change in coach with the national team at the end of 2013 meant a chance of going to the World Cup. With the veteran captain Lucas Neill on his way out, Ange Postecoglou was on the hunt for a centre-back to partner Matt Spiranovic. Young, talented, skilful and able to play out from the back, Sainsbury fitted the bill. It was looking good for the kid from Thornlie, Perth.

But often in football, like in life, fate intervenes. Sainsbury’s debut for the Dutch club PEC Zwolle turned into a horror movie. In his first Eredivisie appearance he fell and collided with a sprinkler that had somehow been left on the pitch. The freak accident fractured his kneecap and spelled the end of his World Cup dream.

Sainsbury later admitted it took him a while to get over that most bizarre of injuries. “It was almost like a bad break-up,” he said in 2016. “You don’t expect that sort of thing to happen on a professional football pitch in Europe in one of the bigger leagues. It’s just crazy.”

With Sainsbury sidelined, Postecoglou’s revamped Socceroos went to Brazil and were beaten in all three group games. They were bold and brave, but fragility at the back was costly and they shipped nine goals, scoring only three. A quick exit ensued. After five months out Sainsbury was back on the park that year and back in the Blauwvingers’ starting XI.

Postecoglou immediately called him up and made him a regular part of his squad. It was a move that paid off handsomely – Sainsbury started all six games as Australia won the 2015 Asian Cup on home soil. His partnership with Spiranovic was crucial as the Socceroos claimed their first major trophy. Suddenly all of Asia was aware of this gangly defender with the jet black hair. Sainsbury won the man of the match award in the final and was selected in the AFC’s team of the tournament, having also played a part in three clean sheets and scored in the semi-final against the United Arab Emirates.

Fast forward just over three years and the defender, 26, is close to his World Cup dream finally coming true. The Dutchman Bert van Marwijk is in charge after a tumultuous year for Australia, in which Postecoglou controversially walked out and the team qualifed for Russia by the skin of their teeth after navigating two tricky play-offs. The former Netherlands coach has said how vital Sainsbury will be to his team. With Spiranovic in the international wildness, he is near irreplaceable.

Facebook Twitter Pinterest Trent Sainsbury in training in Turkey at the end of May. Photograph: Robert Cianflone/Getty Images

The World Cup will be just rewards for a player who has spent more than a decade battling the hard way to break through. At 15 he moved out of home to relocate 3,718 kilometres to the Australian Institute of Sport in Canberra. At 17 he was on the move again, this time 350 kilometres to the Central Coast. At 21 it was to the Netherlands and at 23 to China. Loans to Italy, with Internazionale, and now to Switzerland, with Grasshoppers, have followed. Sainsbury is not your typical footballer but a laconic operator who is more of a throwback to Australian sporting figures of old.

“He’s a bit of a joker and just a real laid-back kind of guy,” his former team-mate Daniel McBreen says. “He’s a consummate professional but he always like to have a laugh or a joke. He wants to get the best out of himself but he also likes to have a laugh along the way as well.”

Practical joker, fun-lover, determined character. Sainsbury might enjoy life to its fullest off the pitch but he means business on it. His versatility has been evident in Switzerland with classy performances in defensive midfield. But his killer focus was most evident last year when his displays helped Australia book their place at the World Cup. He played in all but one of the Socceroos’ matches last year as they navigated through the qualifying minefield.

He was the key to Postecoglou’s much-maligned back three, even while suffering from osteitis pubis – without him the Australia players might be watching their first World Cup on TV since 2002. If the Soccereoos are to have any chance of emulating “the Golden Generation” and getting to the round of 16, a lot will depend on the highly rated centre-back.

John Davidson writes for Guardian Australia.

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