Jurgen Klopp may be prevented from unleashing Liverpool tactic named 'the best in the world'

Andy Cole and Dwight Yorke are famed as arguably the Premier League's best strike partnership in history. Roy Keane and Paul Scholes may take that accolade in midfield while Tony Adams and Martin Keown are regarded the elite duo in central defence.

And when it comes to full-back pairings, Trent Alexander-Arnold and Andy Robertson may not be exceeded. There might not be a more iconic twosome.

Alexander-Arnold and Robertson's prowess to maraud down their respective flank and not only augment attacks but provide another potent threat was a chief factor behind Liverpool's return to the European elite under Jurgen Klopp. Watch highlight reels of the Reds' road to Champions League glory in 2019 and Premier League a year later and a swathe of goals involve Alexander-Arnold and Robertson. There are an abundance of crosses finished off by Mo Salah, Sadio Mane and Co, as well as fine finishes of their own.

It's scarcely a coincidence that both have 58 assists apiece in the Premier League - the joint-most for defenders. They'll continue to keep jostling for top spot as long as they don the Liver Bird on their chest.

Name Klopp's best starting line-up throughout his eight-and-a-half years in the Anfield hot seat and both players' berths are indisputable. Alexander-Arnold has revolutionised the right-back role while Robertson's penchant to relentlessly get up and down the left flank made him arguably the best left-back in the world for a period.

“They are great. I mean they are playmakers as full-backs,” former West Ham boss Slaven Bilic said in 2022. "The way they pass the ball, the decisions they are making, the balls through the lines. It’s unbelievable because when the opponent is pressing you, they let the ball go wide.

“And to have the privilege to have wide players, playmakers, who can play great balls - not just balls to the midfield - but brilliant balls to your strikers that these two are doing week in, week out for four years. They are the best pair of full-backs in modern football."

In total, Alexander-Arnold and Robertson have played 237 matches together. However, despite Liverpool battling for the Premier League title and Europa League crown this campaign - having already claimed the Carabao Cup - they have started just six games together. That is because each player has had respective injury issues.

In the opening four games, Alexander-Arnold and Robertson featured from the outset before the former suffered a hamstring injury in a 3-0 win over Aston Villa on 3 September.

It wasn't until 8 October when they were again named in an XI together during a 2-2 draw at Brighton. The season then paused for the international break, with Robertson suffering a shoulder problem while representing Scotland in a 2-0 loss against Spain.

The former Dundee spent the best part of three months on the treatment table. When Robertson did come back, he started on the opposite wing of Alexander-Arnold in a 3-1 triumph over Burnley on 10 February. Yet in that game, Liverpool's vice-captain sustained a recurrence of a knee injury that has made him unavailable since.

There is hope that Alexander-Arnold make a return in the week following Sunday's visit of Brighton and Hove Albion. The Reds have fixtures against Sheffield United and Manchester United and to have Alexander-Arnold back will be a marked boost to the Reds' ambitions.

Yet Klopp will be braced to be without Robertson yet again. The curse of the international break struck down Liverpool, with the 30-year-old forced off in a 1-0 loss against Northern Ireland. Further tests will be required but Robertson's reaction as he lay on the Hampden Park turf suggested he may be set for a spell on the sidelines.

To Liverpool's credit, they have coped magnificently without Alexander-Arnold and Robertson. Joe Gomez has excelled in both roles, while Conor Bradley has graduated into a fully-fledged first-team member. What's more, Kostas Tsimikas was into a good rhythm before he broke his collarbone against Arsenal two days before Christmas.

And both Alexander-Arnold and Robertson's roles have changed. Alexander-Arnold's remit is now to saunter into the engine room when Liverpool are in possession taking up the hybrid positional impeccably. As a result, Robertson has not been as free-flowing in attack, underlined by the fact he has just one goal and one assist in 20 outings in 2023-24, and has to pick his moments more precisely when fully committing to a foray.