STRANGE to say for a man who once scored the winning goal in a World Cup final, but it is the Champions League that, arguably, has most significantly shaped and defined the career of Andres Iniesta. It was in this competition that he made his Barcelona debut as a raw but promising 18-year-old, a group game away to Bruges in October 2002. Some 14 years later he will hear the Champions League music ring out again as he looks to win it for the fifth time in an already medal-laden career. Should he be declared fit enough to appear, Celtic will face his metronomic majesty in the Camp Nou on Tuesday night.

Mass appreciation arrived late for a player who, even at 32, is showing little sign of slowing down. His achievements have been chronicled in The Artist, a new book that tells the story of his journey from the tiny village of Fuentealbilla to Barcelona’s fabled La Masia academy and on to a glittering, one-club career that has brought him silverware and respect in equal measure. Part autobiography, part biography, the sheer volume of team-mates - both past and present - happy to share positive memories about the player known as The Wise One tells of the esteem in which he continues to be held.

A shy, often reluctant public figure, it is hard to shake the notion that Iniesta would have been the star turn at almost any other club in the world, rather than existing in the shadow of the likes of Leo Messi, Neymar et al. Those who know him best, however, suggest it is a state of affairs that the midfielder is not entirely unhappy with.

“He’s not really someone who has lived out his life in the public domain,” says Sid Lowe, the Spain-based journalist who, along with Pete Jenson, translated The Artist into English. “Even in the book, it’s as much about him, as it is by him. That tells you something significant about Iniesta. Even when he does a book theoretically about him he’d much rather hand over a large chunk of it to others. It’s the same as how he plays; there when he’s needed to be to link it all together without being in the spotlight all the time.”

He has saved most of his talking, then, for the park, most notably in the Champions League. It was Louis van Gaal who gave him his first taste of the tournament, with Iniesta playing all 90 minutes in that 1-0 win in Belgium 14 years ago. He has not forgotten the Dutchman’s influence. “He always had a lot of faith in young players,” Iniesta says in the book. “I owe him a lot and I’m very grateful. I still remember what he said to me in Bruges when I made my debut: 'Go out there and enjoy it. Do what you know best: play football'.

Four years later and Iniesta was a Champions League winner. The only surprise was he had to do it from the bench, manager Frank Rijkaard surprisingly leaving him out of the starting line-up to face Arsenal in Paris.

“When he named the team from the final and I saw that I was not in it, I remember the feeling was a strange one,” he says. “Like I had been cheated, like something had been taken away from me. I didn’t understand.”

Alongside Henrik Larsson and Juliano Belletti, Iniesta would make his mark on the game from the bench.

“Winning in Paris was destiny,” says Victor Valdes, Barcelona’s goalkeeper in the match and Iniesta’s long-time friend. “Everything changed when Andres came on in the second half. He carried the team, taking all the responsibility on his shoulders and we came back to win.”

If that maiden European success was a bitter-sweet experience, then his second Champions League triumph three years later was similarly marred by other factors. Iniesta had secured Barcelona’s passage through to the final with a late winner at Stamford Bridge in the semi-final, a moment so glorious that statistics indicate that birth rates in Catalonia spiked nine months after the match.

But it was a period in which Iniesta was troubled by persistent injury and, in the book’s most startling, opening revelation, a sense of ongoing anxiety and uncertainty. “I felt like I was in freefall, like everything had gone dark,” he says. “I went to find the doctor: ‘I can’t take any more’.” The death of his close friend, the Espanyol player Dani Jarque, in the midst of it all took Iniesta even further into this gloomy place.

“The decision to lead the book with that chapter was a conscious one,” Lowe said. “There’s obviously an editorial reason for that as it grabs the reader’s attention early on but there was also a desire on Andres’ part to put this section first. He wasn’t trying to make a wider point, he just wanted to tell it like it was.”

Iniesta rebounded in the best possible way from that troubling period in his life, scoring the winner in the 2010 World Cup final before revealing a T-shirt dedicating the moment to Jarque. A year later and he had his third Champions League success, with Manchester United again put to the sword in the final. This time there were no negative aspects to dampen Iniesta’s celebrations.

“At Wembley in 2011, Andres reached his peak,” write authors Marcos Lopez and Ramon Besa. “It was the first final he had played pain-free. No stress, no concerns, no discomfort. This time he could just play.”

After a four-year wait, Iniesta’s fourth Champions League winners’ medal arrived last year when Juventus were beaten in Berlin. Now he will go for number five, with a reunion looming with his former hero and manager Pep Guardiola, now with Manchester City. Celtic’s job will be to show they can be more than just bit-part players in the next chapter of the Iniesta story.

- The Artist: Being Iniesta by Andres Iniesta is out now, published in paperback by Headline, £9.99