It is often said in sport that you learn more in defeat than you do in victory.
But in the space of 16 months between May 2015 and September 2016, Maro Itoje became one of the biggest names in world rugby having tasted nothing but victory.
A remarkable 31-game winning streak brought success with England - a Grand Slam triumph in his debut Six Nations campaign and a historic Test series win in Australia - on top of back-to-back Premiership titles with Saracens.
In 2017, those performances for club and country earned him a call-up for the British & Irish Lions series in New Zealand, making him the youngest member of Warren Gatland’s 41-man touring party.
Even six months from now, when Itoje makes his first appearance at a Rugby World Cup, the man who will carry the weight of a nation’s hopes on his shoulders will still only be 24 years of age.
To say his rise has been meteoric would be an understatement.
Today, I'm sitting alongside Itoje back where it all began - Old Albanian RFC, the Hertfordshire club that doubles up as Saracens’ training ground.
We’re here to reflect on one of the most defining victories in his short but illustrious career: the club’s first ever European Rugby Champions Cup triumph.
Sitting alongside Itoje in a worn-out changing room deep in the bowels of the clubhouse, it’s clear that the 2016 final victory over Racing 92 holds a special place in his heart.
“Without it I wouldn’t be here, talking to you, in this illustrious changing room!” he smiles, revealing a glimpse of the schoolboy charm that has earned him the nickname ‘The Pearl’.
Itoje is in candid, relaxed form as we rewatch the moment he held the trophy aloft after his man-of-the-match display in the landmark success.
I take the opportunity to wonder out loud: did this triumph mean more than winning the Grand Slam?
“When you win things with people that you care about, people that you have a genuine interest in and people that have had a big impact on your life, it’s made even sweeter,” he says.
“The team lost a lot of finals and lost a lot of games before we got into this position.
“But in 2016 we felt unstoppable, to be honest. We felt invincible.
"We felt as if no one could come close to us... we were that far ahead of everyone else. That was because we had everyone properly pushing in the same direction.
"It felt incredible to be part of our first ever European win.”
It's easy to forget that just two years earlier, while Sarries were losing their first ever Champions Cup final to a Jonny Wilkinson-inspired Toulon, Itoje was playing in front of 80 people for Old Albanian in St Albans.
The following season, he had only been in the Saracens first team for a matter of months when the London club suffered semi-final heartbreak at the hands of Clermont Auvergne.
But for Itoje to say he was merely ‘a part’ of the club’s crowning glory is typical of a man who exudes a quiet humility in everything he does.
It quickly occurs to me that the modest setting for our interview is a fitting backdrop for his self-effacing demeanour.
There was nothing modest, though, about his display against Racing on May 14, 2016.
On a miserable day in Lyon at the newly-constructed Grande Stade de Lyon, Itoje produced a titanic performance to help Saracens take their place at the top table of European rugby and crown a remarkable breakthrough year on a personal level.
In the lead-up to the game, the column inches had been dominated by another man making his Champions Cup final debut: Dan Carter.
The All Black legend was looking to complete a clean sweep of major club and international honours, just ten months after leading New Zealand to a record-breaking third World Cup triumph.
“We heard rumours that he wasn’t quite 100 per cent,” says Itoje.
“But Dan Carter at 70 per cent is better than most people at 100 per cent.
“We knew he was still going to be a very dangerous player and if we allowed him to do what he does then it would have been a very long day for us.”
In the end a half-fit Carter struggled to make any meaningful impact on the game, delegating kicking duties before being forced off just after half-time.
The man expected to have a defining influence on the game was instead a bit-part player as the battle for Europe’s top prize was decided in a heavyweight tussle in the pouring rain.
A game that had been billed as Carter’s swansong became a battle for territory.
Suddenly, Itoje was thrust to the centre of club rugby's grandest stage.
For once the Saracens forwards were dwarfed by a gargantuan Racing side that featured the likes of Chris Masoe, Luke Charteris and the 24-stone colossus, Ben Tameifuna.
But weight disadvantage was not enough to faze a team that lived by the 'Wolfpack' mentality – a nickname first coined by Paul Gustard, Saracens' former coach and defence mastermind, in 2014.
“The wolfpack was the analogy we used because an individual wolf on its own is strong, but when you have a pack of wolves together they can take down almost anything,” explains Itoje.
“The pack can take down individuals or teams that are potentially stronger and better than them.
“If they’re not as united and they don’t work well together, they fall short against the wolfpack.
“It was quite a powerful analogy because it used our defence as a way of overpowering teams.
“We’ve played against numerous teams, exceptional players and exceptional individuals, but we beat a lot of those teams because we worked as a collective rather than as individuals.”
Itoje reveals that Saracens' forwards wanted to lay down an immediate marker to prove they wouldn’t be bullied by Racing’s mammoth eight.
An early lineout provided the perfect opportunity.
"There are numerous ways to stop a maul and we had a plan of unsettling them a little bit,” Itoje explains.
“We wanted to put them in a position we wanted them to be in and then see how they reacted.
“We sent Mako [Vunipola] in to smash the legs of the ball carrier and then everyone else piled in.
“If you look at the outcome of it, it was probably a win for us - they didn’t really get any momentum.”
That moment set the tone as Saracens physically overwhelmed their French opponents on a day that required every man to put their body on the line for the cause.
No one epitomised that thirst for the fight more than Itoje.
The lock had already forged a reputation for producing what Saracens’ forwards coach Alex Sanderson described as "Hollywood moments": tackles, turnovers and lineout steals.
In an evenly-matched game that would be decided by winning the small battles – a big hit here, a remarkable interception there - The Pearl was in his element.
“That’s my game: live by the sword, die by the sword,” says Itoje.
“My game is about living on that edge. The way I play is very abrasive… a very physical type of game.
“Unfortunately I’m not blessed with the skills that some of my team-mates like Alex Goode and Owen Farrell have. It's about a lot of effort and being at the forefront of everything.”
Itoje was indeed at the forefront of the action in a cagey first half.
With 30 minutes gone and just three points separating the two sides, he managed to disrupt a Racing ruck.
Using his athletic prowess to step over prone bodies on the floor, Itoje kicked the ball clear, allowing flanker Henry Fraser to reclaim possession for Sarries.
That particular counter-rucking move has since been outlawed - "A big shame, to be honest!” Itoje laughs ruefully - but it proved a pivotal contribution at a crucial stage of the game.
The next passage of play would see Farrell extend Saracens’ lead at the break with another penalty.
Eight minutes after the interval, with the scoreline well poised at Racing 6-12 Saracens, Itoje came up with another momentum-swinging play to hand his side the initiative.
Pinned inside their own five-metre line by Farrell’s deft grubber kick, Racing lock Charteris spilt the ensuing lineout. Itoje reacted fastest, pouncing on the loose ball to reclaim possession.
Not content with the intervention, Itoje hit three of the next four attacking rucks before Racing were penalised in front of the posts, allowing Farrell to extend the north Londoners’ lead by another three points.
Itoje’s all-action approach carried a certain element of risk, especially on such a greasy surface where the margin for error was so small.
In one heart-in-mouth moment, he attempted to block a grubber kick by sliding feet first to prevent the ball from being played in behind Sarries’ blitz defence.
It’s a technique that would later generate widespread controversy after he employed it successfully during a Premiership clash with Leicester in January 2017.
In an interview on BT Sport’s Rugby Tonight, his Saracens teammate George Kruis revealed Itoje's fondness for the move even briefly saw him nicknamed [Paolo] ‘Maldini’, in reference to the legendary Italian footballer.
This time, however, the 21-year-old’s timing was out and he narrowly avoided a potential sin-binning for tripping an opponent.
It’s a moment that encapsulates the fine line Itoje walks between success and failure, hero and villain.
“I’d done that a few times and had success with it so I thought I’d give it another go!” he grins.
“I’ve got better at it as I’ve got older. It’s all about game understanding, understanding the context and the possible consequences of your actions. I think that was just a reactionary thing to try to block the grubber.
“Sometimes you can go in for a 50-50, but if it goes wrong – and I know referees are highlighted to the stuff I do now - I have to understand the potential ramifications of my actions and the negative pressure I can put my team under.”
As we watch the key moments of the game back together, I’m struck by Itoje’s tirelessness.
He’s everywhere, influencing the action on both sides of the ball.
“The thing is… often you’re tired, and your mind tells you that you’re tired but your body can keep on going, so just you need to keep on going,” says Itoje.
“Especially when there’s the prize of the Champions Cup to win… if you’re lacking that motivation you need to find it from somewhere because there’s 14 other people on the pitch who you don’t want to let down.”
With just six minutes left on the clock, Sarries could almost taste glory - even if their position remained precarious.
Three penalties from the boot of Farrell had given the English champions a six-point lead, but Racing remained one converted score away from snatching victory.
In a rare second-half foray into Racing’s half, Saracens forced a lineout that was crucial to secure if they were to retain their advantage.
Hooker Jamie George threw to the back, where Itoje rose high to take the ball, setting up a rolling maul that would lead to a sixth successful penalty for Farrell, putting the London club to within touching distance of immortality.
Unsurprisingly, Itoje, who had relatively little big-match experience to that point, is quick to wave away his involvement in such a clutch moment.
I ask him whether he demanded the ball, backing his ability to pull off a game-defining play.
“I like to think of myself as a guy who enjoys the big moments but it’s always team first,” he says.
“George [Kruis] was the lineout caller in this situation, if I remember correctly.
“When you’re calling a lineout it’s all about calling into space.
"It’s not about having an ego or jumping because I want to jump… it’s all about trying to win it for your team.
“It’s always ‘what’s best for the team?’, not ‘what’s best for me?’ or ‘what’s going to make me look good?’"
With just three minutes remaining on the clock and Racing camped inside their own five-metre line, requiring two scores to overturn Sarries' nine-point lead, Itoje managed to disrupt another ruck with his foot.
He watched the final moments from the sidelines after being substituted in the 79th minute, but not before being named man of the match for the third successive game, having also scooped the award in the quarter-final and semi-final wins over Northampton and Wasps respectively.
With the seconds ticking away, Racing desperately tried to pummel their way out from beneath their own posts, but hooker George got his hands on the ball and referee Nigel Owens penalised Juan Imhoff for holding on.
In the background, Kruis, Itoje’s lock partner, collapsed to his knees and beat the ground with his fists: the game was won.
Farrell completed the formalities by slotting home his seventh penalty of the match to seal a 21-9 victory.
Saracens were European champions for the first time in their history.
The Wolfpack also became the first group of players ever to lift the trophy with a perfect winning record.
What was Itoje thinking about as the clock ran red?
“The party!” he quickly shoots back with a smile.
My next question is inevitable, then. Was the celebration as phenomenal as the achievement?
“We had a good time,” chuckles Itoje.
“That was in Lyon, so we went back to the hotel and the club put on a little party with food and drink for families and everyone involved, which was cool.
“Our party man or club hype man is probably Richard Barrington.
“He loves a little sing-song. He’s here partly to play rugby and partly to orchestrate all the chants!
"He’s a great man to have around. He’s always in the middle singing, drinking and all that kind of stuff.
“The next day the boys met up together and had a good time celebrating.
"But we quickly had to revert our attention back to the following week because we had Leicester Tigers at home in the semi-finals [of the Premiership]. So we couldn’t party for too long.”
Itoje admits with refreshing honesty that the high of playing a starring role in his boyhood club’s maiden European triumph also presented unexpected difficulties, initially at least.
With a domestic semi-final just seven days away, the Wolfpack had little time to draw breath in their quest to become the first English side since Lawrence Dallaglio’s 2004 Wasps to win a league and Champions Cup double.
“That was the first week in my playing career where I found it hard to get myself motivated to play,” Itoje says.
“We had reached such a euphoric high to get to a place we’d never been before, where we were champions of Europe.
“To then come back down to planet earth, to ground zero, to play a semi-final against a team who were very motivated to beat us was tough to get up for.
“In the end we probably didn’t play as well as we could’ve done, but because we were so good that year we had enough to get through."
But rugby, like any sport, never stands still - and the club were already looking ahead to how they could build on their success.
“This is just the beginning,” said chief executive Nigel Wray after the win over Racing, comparing his core of young English players including Itoje, George, Billy Vunipola and Farrell to Manchester United’s 'Class of 92'.
“People forget that we’ve got 17 English players. What’s exciting is that they can go on for the next five years.
"They’re young lads and, wow, that’s what it’s about. It’s a bit grand to use the word ‘dynasty’ but let’s just say we want to do bloody well.
“While winning the European Champions Cup was great, there is more.
"It is a strange word for rugby but they love each other. They really do love each other, which means they want to pull out that extra bit for each other. That’s the difference.”
His prophecy would prove spot on.
A year later Saracens retained the trophy, defeating Clermont 28-17 to cement their status as a true modern dynasty.
During our interview, Itoje, typically, is not inclined to dwell for too long on the more nostalgic elements of his remarkable career to date.
Not when there are so many more mountains left to climb.
“There’s only so long you can reminisce," he says.
“You definitely have to enjoy the moment - it’s a crucial part of what we do - and I’ve definitely enjoyed every moment so far.
“But once it’s gone you have to switch on to the next job.”
The next job for Saracens is Saturday's Champions Cup final at St James' Park, Newcastle.
In their way stand reigning champions Leinster, who beat the Londoners in last season's quarter-final en route to a fourth European Cup.
“Rugby doesn’t wait for anyone,” he adds with a knowing shake of the head.
The Pearl, it seems, has wisdom beyond his years already.
He is determined to make hay while the sun shines - and only a brave man would bet against him succeeding.
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