The importance of full-backs in the modern game cannot be stressed enough. Managers demand that their full-backs be proficient in attack while also being good defensively.
In recent years, there has been more focus on having the correct full-back pairing, ensuring that they collaborate well with each other and are on a similar wavelength.
Top five full-back pairings in history:
Over the years, there have been some phenomenal full-back pairings who played key roles for their teams and enjoyed storied careers, both domestically and at the international level.
On that note, let's take a look at the five greatest full-back pairings of all time.
#5 Trent Alexander-Arnold and Andrew Robertson (Liverpool)
Liverpool might not be in a good position right now. But it is easy to forget that Jurgen Klopp's men won the Premier League last season and the Champions League the campaign before that.
Crucial to their success has been their full-back pairing of Trent Alexander-Arnold and Andrew Robertson. Alexander-Arnold is a product of the Liverpool academy, while Robertson cost Liverpool £8 million, buying him from Hull City in 2017.
Highly creative and attack-minded, the pair has been key to Liverpool's dominance under Klopp. The Reds play with midfielders who are not renowned for their creative play; so much of Liverpool's attack is dependent on their full-backs bombing forward to provide good crosses or quality passes.
Robertson and Alexander-Arnold enjoy a good friendship off the field as well. Both are regarded as two of the best in their positions. But it is essential that Liverpool don't overwork them, as they play pretty much every game when they are available.
#4 Dani Carvajal and Marcelo (Real Madrid)
Real Madrid's success under Zinedine Zidane is often credited to the likes of Cristiano Ronaldo, Toni Kroos, Luka Modric, Karim Benzema and Sergio Ramos, but their full-backs very rarely get the praise they deserve.
Marcelo joined Real Madrid in 2007 from Fluminense for a fee of £6 million, while Dani Carvajal is a product of the Real Madrid academy, who returned to the club from Bayer Leverkusen in 2013 for £6 million.
Real Madrid won three consecutive Champions League titles under the management of Zidane, with Marcelo and Carvajal starting all three finals. While Marcelo is renowned for his attacking play and has strong technical qualities, Carvajal is a reliable presence at right-back and has good passing ability.
Both players are still at Real Madrid. The 32-year old Marcelo's prowess has reduced in recent seasons, while the 29-year old Carvajal has had his injury issues this campaign.
Real Madrid have sold talented full-backs like Achraf Hakimi, Sergio Reguilon and Theo Hernandez in recent transfer windows, so it remains to be seen what their plan regarding their veteran full-backs is.
#3 Gary Neville and Denis Irwin (Manchester United)
Two of the most important players at Manchester United during their prime, Gary Neville and Denis Irwin, were reliable full-backs who consistently started for the Red Devils.
Neville was a product of the famed Manchester United academy, while Irwin joined the club from Oldham Athletic in 1990 for a fee of £630,000. The two players made over 500 appearances in all competitions for Manchester United.
Neville was a hard-working, aggressive right-back whose determination and leadership ability were well known.
Meanwhile, Irwin was a calmer presence at left-back, with his consistency rated highly by Sir Alex Ferguson. Such were Irwin's performances at left-back that he was a starter for the club even during his 30s.
Irwin departed Manchester United in 2002 after 12 trophy-laden years and joined Wolverhampton Wanderers. Neville, meanwhile, was a one-club man who retired in 2011.
#2 Cafu and Roberto Carlos (Brazil)
Both Cafu and Roberto Carlos enjoyed incredible club careers. But their impact at the international level was extremely visible, as they were mainstays for the Brazil national team for a while.
The full-backs made more than 100 appearances for Brazil and were part of the team that won the Copa America twice (1997,1999) and the FIFA World Cup in 2002.
Carlos was an extremely attack-oriented left-back. He was blessed with strong physical qualities and good speed and is regarded as a legend of Real Madrid. Similarly, Cafu is seen as one of the best right-backs to have played the game, with his intelligence, technical skill and crossing prowess all crucial for both club and country.
Both players retired from national duty in 2006 but went on to represent their clubs for a while. Cafu retired as a player in 2008, while Carlos did so in 2015.
#1 Mauro Tassotti and Paolo Maldini (AC Milan)
The entire AC Milan backline under the management of Arrigo Sacchi and later Fabio Capello earned legendary status. Two of them, full-backs Mauro Tassotti and Paolo Maldini, played an important role in the club's success during that time.
Maldini was a product of the AC Milan academy, while Tassotti was signed from Lazio in 1980. The defensive line of Tassotti, Franco Baresi, Alessandro Costacurta and Maldini is regarded as one of the greatest backlines of all time, with their defensive dominance playing a key role in Milan's incredible trophy-laden stint.
Tassotti was capable of operating as a centre-back when necessary, while Maldini was renowned for his crossing prowess and composure as a left-back. In his later years as a centre-back, Maldini established himself as one of the greatest defenders to have played the game.
Tassotti made 583 appearances in all competitions for Milan, while Maldini, a one-club man, made more than 900 appearances in all competitions for the club.