As the full-time whistle blew at St Mary’s, Arne Slot, situated at the back of the press box, may have let out a huge sigh of relief. It needn’t have been such a frantic and nervous ending.

At half-time, with Liverpool two goals ahead and cruising, that seemed unlikely. But a determined second-half display from Southampton meant that the latter stages of the 2-1 win looked anything but assured. Had Jarell Quansah’s pull back on Mateus Fernandes been punished in injury time, it could have been a very different story on the south coast.

But that lackluster ending took the shine off a night that actually contained many positives for Liverpool. That the second-half display dipped so markedly was due in part to the withdrawals of Trent Alexander-Arnold, Joe Gomez, Alexis Mac Allister and Cody Gakpo, clearly with an eye towards this weekend’s Premier League trip to Tottenham Hotspur.

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That so many players were rested or replaced early was a huge plus point for Slot, as was the return from injury of Kostas Tsimikas, Federico Chiesa and Jayden Danns. Harvey Elliott’s excellent display was perhaps the most encouraging aspect of the night, with the 21-year-old scoring and putting in a player-of-the-match display as the Reds progressed to the semi-finals.

That Darwin Nunez - amid chants of his comparison to Andy Carroll - tucked the ball in for the opening goal of the night was also hugely positive, as was the tactical flexibility shown by Slot, with Wataru Endo moving from defense to midfield and Liverpool controlling the game prior to the second-half changes.

The team that ended the match was youthful, to say the least. In fact, six were aged 22 or younger, while nine of the matchday squad fell into that category. Of that juvenile cohort, 17-year-old Trey Nyoni perhaps turned the most heads.

Starting his first-ever match for the senior team, he didn’t look out of place. Nyoni helped Liverpool maintain its rhythm and structure in the early stages, while also playing some progressive passes into the offensive areas. It was an encouraging start for the youngster and it’s unlikely to be the last time we see Nyoni in the team.

Wednesday’s game was also an indication that, like Jurgen Klopp, Slot values the importance of youth and bringing through the club’s academy players. That this insight came in the Carabao Cup is ironic given Liverpool’s run to the final last season was dominated by the inclusion of youngsters in the team.

Quansah, Danns, James McConnell, Lewis Koumas and Bobby Clark all came on in the final victory over Chelsea in February and three of that group could earn a second winners’ medal in the competition later this season.

Wednesday’s win was not just a reminder of how valued Liverpool’s star men are, but of the plethora of encouraging talent currently being cooked up in Kirkby.