It didn't take long for Liverpool's cautious stance to be swiftly justified.
With Joel Matip joining long-term injury absentee Ibrahima Konate on the sidelines, worries over the fitness of Joe Gomez meant that, just two games into last season, Jurgen Klopp was compelled to partner Nat Phillips with Virgil van Dijk at the heart of defence for the visit of Crystal Palace.
Far from being a luxury, having a fifth senior centre-back was a necessity, Liverpool mindful of the troubles of the 2020/21 campaign when a catalogue of injuries in the position saw Academy graduates Phillips and Rhys Williams guide the Reds over the finishing line to an unlikely Champions League qualification.
Konate was bought within days of that season concluding. And now, two years later, Liverpool are again considering refreshing their central defensive options.
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The situation, though, has evolved significantly from just 12 months ago, as evidenced by the issues of last campaign when Liverpool leaked 47 Premier League goals - their highest such tally in a full season under Klopp. Indeed, in 52 games in all competitions, the Reds conceded at least three goals on 11 different occasions, the first time that had happened since 1964/65.
Of course, some of that was down to the midfield problems that plagued the Reds, particularly during the first half of the campaign, but the chopping and changing at centre-back didn't help, demonstrated by the first-choice pairing of Van Dijk and Konate starting just 17 games together, 11 of which were won.
The next most used partnership was Van Dijk and Gomez, which won seven and lost five of 13 starts, with Van Dijk and Matip winning six of 10 games starting alongside each other and losing just one. The remainder were Matip and Gomez (four games, one win), Matip and Konate (three games, no wins), Konate and Gomez (three games, one win), Van Dijk and Phillips (one draw) and Phillips and Gomez (one win).
While Phillips only made two starts and a further three substitute appearances, the remainder were all given significant game time throughout the season, with Gomez also featuring at right-back on a few occasions. But with Van Dijk and Matip both in their thirties - and the latter in the last year of his contract - any new arrival would most likely be given greater opportunities than Phillips.
And, in terms of numbers, Liverpool may require imminent reinforcement. Williams is spending the campaign on loan at Scottish Premiership side Aberdeen while, after flirting with a departure for several transfer windows, Phillips is expected to leave on a permanent deal. Championship side Leeds United and Dutch outfit Feyenoord are interested although the Reds may have to lower their £10million asking price.
As with Konate, Liverpool are looking not quite for the finished article, but for a younger centre-back with sufficient potential to improve and enough experience to cope with being thrust into first-team consideration.
The players are certainly out there, even if availability isn't always quite so straightforward. While Mickey van de Ven of Wolfsburg was linked earlier in the summer, Liverpool haven't pursued any deal while Torino's Holland international Perr Schuurs - who the Reds assessed during his time at Ajax - is one of several other players of which the recruitment team are aware.
The ideal target, though, remains Chelsea's Levi Colwill, with the ECHO having reported back in March of Liverpool's admiration of the player. The 20-year-old impressed on loan at Brighton & Hove Albion last season and recently helped England win the UEFA Under-21 Championship without conceding a goal in the tournament. Homegrown, aged just 20 and a left-sided defender with Premier League experience, Colwill ticks almost every box Liverpool require.
Ultimately, though, it will be down to the desire of the player and the plans of new Chelsea boss Mauricio Pochettino whether Liverpool can realistically pursue a deal in the coming weeks.
But whoever Liverpool next recruit in defence - whether it be this summer or beyond - they will be expected to become the bedrock of the Reds' future rearguard. The centre-back pecking order is about to change for good.
