With Andy Robertson entering his thirties and Kostas Tsimikas now 28, the left-backs are getting older. All have performed at a high level and continue to show that they are among the best in the Premier League.
However, a generational change is inevitable for the future, and there is interest in European left-backs in addition to Premier League players such as Wolverhampton Wanderers defender Rayan Aït-Nouri and Fulham defender Antonee Robinson.
According to international media outlet AS, Liverpool have shown a strong interest in Spanish U-21 defender Alvaro Carreras, who has been playing for Benfica this summer, leading a battle with Real Madrid and Barcelona.
The Spanish defender was signed by Manchester United until last season, but failed to make a first-team appearance for the club. Loans at Preston North End and Granada followed, and he was released by the Portuguese club this summer.
The left-back, who has been compared to Bayer Leverkusen defender Alejandro Grimaldo, has been used regularly this season and has started against Red Star and Atletico Madrid in the Champions League.
Only Liverpool, who are rumoured to be linked with a number of defenders, including left-footed centre-backs, do not know which player is the real deal. To begin with, left-back seems a low priority, a position where a long-term successor to Virgil van Dijk or a potential replacement for Mohamed Salah should be the first to be dealt with.
Will Liverpool go ahead and try to acquire a young Spanish side-back…?