#3 Achraf Hakimi and Aleksandar Kolarov (Inter Milan)
Unlike the other full-back combinations in this list, we're yet to witness Achraf Hakimi and Aleksandr Kolarov play together. That is because they're Inter Milan's newest recruits, but they surely appear to be an exciting pairing on paper and one to look forward to in the 2020-21 season.
After struggling to force his way into Real Madrid's first-XI, Hakimi developed into one of the most exciting prospects at Borussia Dortmund, making 17 assists and scoring 12 times during two memorable seasons on loan at the Signal Iduna Park.
The Moroccan star, predominantly a right-back, impressed even when played in the right wing-back position on various occasions, which makes him an ideal option in Antonio Conte's system; Kolarov, despite his age, could also be key for the Nerazzurri.
In 100 top-flight appearances for AS Roma, Kolarov struck 17 times and laid 16 assists - no full-back had more goal-contributions in the Serie A during that period. Thus his arrival adds extra bite to Inter's attack while his set-piece skills and big-game pedigree too will come in handy for the Milan-based club.
#2 Benjamin Pavard and Alphonso Davies (Bayern Munich)
Bayern Munich's treble-winning campaign last season saw an influx of several talented youngsters bursting onto the scene with the senior team; two of them - Benjamin Pavard and Alphonso Davies - forged an excellent full-back partnership to take everyone by surprise.
Signed from Stuttgart last summer, Pavard, who shot to fame for his performances in France's World Cup-winning campaign in 2018, was quick to establish himself in Bayern Munich's setup and made a huge impact at both ends.
He was directly involved in nine goals in the Bundesliga, scoring four and assisting five, while he also helped shore up the backline by tucking in whenever his counterpart Davies drove forward, which in turn brought composure and class to the Bayern back-four.
Davies, on the other hand, emerged as the most exciting talent last season, impressing with his electrifying speed and nimble footwork. He completed more dribbles than anyone in the German top-flight while his eye-catching performances in the Champions League has made him a favourite for the 2020 Golden Boy award.
#1 Trent Alexander-Arnold and Andrew Robertson (Liverpool)
Liverpool's indomitable rise to the pinnacle of football glory under Jurgen Klopp is down to an immense collective effort, especially from their marauding full-backs, Trent Alexander-Arnold and Andrew Robertson, who are already considered one of the best pairings of this century.
Alexander-Arnold is redefining the role of a full-back with his creative brilliance, setting the record for most assists by a defender in the 2018-19 season with 12 before going one better last season to break his own record as the Reds romped to their first Premier League title.
His sublime technique, intelligence and extensive passing range are crucial in Liverpool's play while his exceptional ability with set-pieces has added a new dimension to the side's already blistering attack.
On the opposite flank, Robertson has evolved into one of the most industrious full-backs in the division, with his energy and work-ethic firmly establishing him as an Anfield favourite. His imperious crossing ability saw him rack up 12 assists last season, the most in the Premier League, or for that matter in Europe's top-5 leagues, by a defender after Alexander-Arnold.