Full-backs do not traditionally dominate the headlines, but they are more important than ever in the modern game. With help from legendary left-back Roberto Carlos, Nick Wright examines how the least fashionable position on the pitch has become integral to success...
It didn't seem funny at the time, but two decades on Roberto Carlos can crack a smile as he remembers the events that led to his departure from Inter Milan in 1996.
"I had a little problem when I was at Inter," he tells Sky Sports. "I'm a Brazilian and I love to attack, but they wanted to play with four defenders who weren't allowed to go forward."
The exciting young Brazilian had only arrived in Italy a year earlier, but Inter manager Ottavio Bianchi had been unexpectedly replaced by a certain Roy Hodgson, who felt he lacked the defensive discipline to play as a full-back. Roberto Carlos was used on the wing, up front and even in central midfield. By the end of the campaign, he'd had enough.
After voicing his frustrations to owner Massimo Moratti, Roberto Carlos was sold to Real Madrid, where Inter would watch him blossom into one of the world's greatest ever full-backs, winning four league titles, three Champions League trophies and a host of other honours.
It was a fateful misjudgement which came to define Hodgson's reign at Inter, but the Englishman was not the only one who had doubts about his buccaneering style. In Europe, the idea that a full-back should be defensively-minded was not unusual. Roberto Carlos was ahead of his time.
At Madrid, though, Fabio Capello was willing to break from tradition - and his own habits - in order to play to the Brazilian's strengths. "Capello had specific plans for him," writes Gabriele Marcotti in Capello: Portrait of a Winner. "He didn't view him as a defensive weapon, but as an attacking one, albeit from deep-lying positions."
Roberto Carlos explains: "At Madrid, we managed to change the way full-backs played. Christian Panucci was more defensive on the right, but Capello wanted me to attack. It was about movement. When one went up, the other stayed back to provide cover. It was the same with me and Cafu in the national team. It was easier for us - and it worked."
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Roberto Carlos immediately became a key player in a team full of Galácticos, dominating Real Madrid's left flank for over a decade. His electrifying speed and endless stamina allowed him to score and create goals at one end while preventing them at the other. As Vicente del Bosque once put it: "Roberto Carlos can cover the entire wing all on his own."
His successor Marcelo now plays with the same attacking adventure, and the decision to liberate Roberto Carlos was influential in a wider context too. Gradually, the game began moving away from the old, conservative approach. From Ashley Cole at Arsenal to Dani Alves at Barcelona, attacking full-backs became increasingly prominent among Europe's elite.
It is only in the last few years, however, that the evolution has truly accelerated in England. This season, Antonio Conte's 3-4-3 has placed extra emphasis on Marcos Alonso and Victor Moses at Chelsea, Danny Rose and Kyle Walker have been among the Premier League's standout performers at Tottenham, while Hector Bellerin's attacking threat has marked him out as the world's best young player in his position at Arsenal.
Full-backs can be seen bursting into the final third up and down the country, and the stats highlight the shift in emphasis. As recently as 2011/12, there were only five full-backs in the Premier League who created 20 or more scoring chances. Since then, the number has shot up. In 2015/16, there were 21. This season, the number already stands at 12.
Patrick van Aanholt is among them. His £14m move from Sunderland to Crystal Palace shows that attacking full-backs are even highly valued in a relegation battle. Indeed, when asked about the Dutchman's arrival at Selhurst Park, it was notable that Sam Allardyce immediately referenced the four goals and three assists that helped Sunderland avoid the drop last season.
Priorities have changed. Instead of using traditional wingers who hug the touchlines, many teams now look to their full-backs to provide the width. It started with Capello at Madrid when he instructed Raúl to drift inside from his starting position on the left in order to free up space for Roberto Carlos to bomb into. What was once an unusual tactic is now common place.
"Now we see that teams everywhere play very compact in order to create space for the full-backs to go forward," says Roberto Carlos. "Defensive qualities are still important, but now you need power and technique in that position. You need to defend and attack."
If Roberto Carlos was the archetypal attacking full-back, then Gary Neville typified the different breed. Neville could deliver dangerous crosses on the overlap, but his defining strengths were not technical or physical. Above all, he was an intelligent, disciplined and dedicated defender. In 19 seasons at Manchester United, he won more titles than he scored goals.
Full-backs in Neville's image are few and far between nowadays, and with the emphasis changing and coaching becoming more technically-focused, they will only become rarer in the years ahead. It's something the Sky Sports pundit touched on in a fascinating column for the Daily Telegraph in October 2014.
"With old school coaches, 60-70 per cent of your training ground work would be defensive," Neville wrote. "Where your foot would be, the position of your hips, how often you would have to turn your head to avoid ball-watching. I compare it to a musician stripping a song back to its elements. I started off with a high defensive base. Players now are starting out with a high technical grounding and learn the defending later."
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Neville recalled his formative years under Eric Harrison and Nobby Stiles in United's youth teams. "We did a game called man-to-man marking, down the whole length of the pitch, whereby you could tackle only that man," he wrote. "What it came down to was recovery runs when you gave the ball away. If your man scored you would embarrass your whole team and there was no hiding place."
Neville paints a picture of an uncompromising environment in which the coaching was "brutal" and a full-back allowing a cross was seen as a crime. It steeled him for the challenges ahead and made him the defender he was, but it contrasts sharply with what Danny Rose said about his progress under Mauricio Pochettino at the end of last season.
"As daft as it sounds, I had never had a manager work on me until Mauricio Pochettino came to Tottenham," he said. "It wasn't until he came in that I had anyone work on me as a left-back and help me improve.
"The boss always says that he wants me to play with the same arrogance as Marcelo at Real Madrid. Every time Marcelo goes out onto the pitch he looks like he thinks he's the best in the world. Pochettino wants me to have the same arrogance when I play for Spurs."
It's a jarring comparison which highlights just how much the role and requirements of a full-back have changed, and it also explains why Premier League goals are on the up. With the growing emphasis on attacking from the back, this season's average of almost three goals per game is in fact the highest in the history of the competition.
But even now, in an era when the best full-backs are primarily offensive weapons, striking the right defensive balance remains key. Walker and Rose have claimed nine Premier League goals and assists between them and rank second and sixth among defenders for open play chances created with 31 and 23 respectively, but they have also helped Spurs keep the best defensive record in the division.
A total of just 16 goals conceded in 23 games is one fewer than leaders Chelsea, whose wing-backs Alonso and Moses have been similarly effective. The 3-4-3 formation gives them even more licence to attack, allowing them to contribute 11 goals and assists between them, but they too have been vital at the other end.
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It's like Roberto Carlos said. You need to defend and attack. You need power and technique. The Brazilian found a culture resistant to his style when he first arrived in Europe all those years ago, but Inter Milan's loss was Real Madrid's gain. Two decades on, the role of the full-back has changed forever.