Whenever the sweeper is mentioned nowadays, it's generally in a historical context or perhaps by someone with a penchant for elegant defenders, dreaming of the halcyon days of Gaetano Scirea, Franz Beckenbauer and Franco Baresi.
But with the three-man defence enjoying a renaissance across the globe, it's time more attention was paid to how that system works, and consider the benefits of a modern incarnation of the libero.
If used correctly, the benefits are obvious. The sweeper is a free, creative influence at the back who can add extra strength while defending before then beginning the counter attack. The obvious problem is that finding a player with the required attributes—strength, speed, defensive prowess coupled with intelligence, good passing skills and ball-carrying abilities—isn't easy.
Despite their exclusivity, there are several players already plying their trade in Europe's top leagues who fit the bill and who could be used by an enterprising manager to revive the lost art of the libero. Read on to find out who.
Some teams use a sort of inverted sweeper when in possession of the ball, that is to say a defensive midfielder who drops back into the defence and allows the full backs to press forward as part of the attack.
Roma's Daniele De Rossi is particularly effective at this, while there are also several players who've been used in that role at Barcelona in recent years. In many ways, this is a logical development from the introduction of the offside rule and modern tactical ideas.
Hardly surprising, then, that classic sweepers like Lothar Matthaus started their careers farther up the pitch.
Debate continues about David Luiz's best position mainly for this reason. The Brazilian is comfortable as a centre-back and in the midfield, even though his libero-like qualities don't really fit in with the stereotypical characteristics normally associated with either role.
The creative bravado with which he plays has its detractors, and in the past, it has cost Chelsea when Luiz switched off. Paired with more restrained, conservative defenders, he would be free to express himself.
Not unlike Luiz, the jury is still out in some quarters as to how to best use Phil Jones.
The young Englishman is bursting with obvious—albeit sometimes flaky—potential. He's athletic and versatile, and he adapts to other positions better than most 21-year-olds would.
That's why he'd be an interesting libero experiment for David Moyes. Paired with a couple of traditional centre-backs, Jones would be able to use his substantial defensive capabilities when called upon at the back while also working more on his passing and his skills on the ball so that he can contribute going forward.
Such a role might get the best out of Manchester United's protege and give them a unique defender without having to overly restrict the player—something that might result in frustration or the occasional switch-off for someone with greater abilities.
It's rare that a teenage defender goes for headline-grabbing sums, but Marcos Aoas Correa, better known as Marquinhos, is no ordinary teenage defender.
The Brazilian played just one season in Serie A for Roma before being snapped up by Paris Saint-Germain for around €35 million.
It's an incredible figure for a player with so little experience at the highest level, but Marquinhos has everything needed to become one of the world's great players. He's quick, good on the ball and an excellent passer. His work rate is also admirable, and he is capable of covering huge distances during the course of a game.
In many ways, Sergio Busquets is a great example of what a libero needs to do. Except, of course, for the fact that he plays in front of the centre-backs as a defensive midfielder.
The Spaniard is better defensively, but by dropping back, he allows the other defenders to press forward when in possession. In that sense, he's actually part of a libero partnership with Gerard Pique, who is a much more accomplished attacker and far more comfortable on the ball.
Like De Rossi at Roma and for Italy, Busquets can play as the last man while others get more involved in the attacks and then drift back farther forward to break up the opponents' attacks when not in possession.
He's played all across the back four for club and country and is comfortable in defensive midfield. Germany and Bayern Munich's Philipp Lahm is one of the most complete, compelling footballers in the world today.
Lahm isn't the most committed tackler in the world, but every other aspect of his game would lend itself perfectly to deployment as a libero, from his concentration and creativity to his passing and versatility.
And how fitting would it be to see another Bayern player resurrect the role that Beckenbauer so famously pioneered in the 1960s and '70s.
Parma's Marco Parolo is another midfielder who could be used in a libero experiment. The 29-year-old is an excellent tackler, he's good in the air, and he rarely gets caught off guard.
On top of that, he's a constant goal threat for the Crociati, notching up three assists and six goals in Serie A so far this term.
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