For Liverpool, it was a night of positives. While the gap in scoreline was ultimately narrow, there was a clear gulf — even with all the changes and the makeshift defense — to Southampton, with a place in the semifinals successfully booked.

By the second half of his Anfield tenure, Jurgen Klopp had ended up making a habit of being in the final throes of domestic cup competitions. Arne Slot, though he wasn't on the touchline here, has done so immediately.

Like Klopp, he chose to go with the youthful players and those who are more on the periphery on his roster in the main. Trey Nyoni faded in the second half but slotted right in during the first, and Tyler Morton was very accomplished in midfield, doing a job at full-back too. Off the bench, James McConnell and Jayden Danns played their part.

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Making it 20 wins from his first 24 matches in charge, this was a new test. Was it the so-called "Klopp factor" that allowed Liverpool to field a team made up of young talents and out-of-position stars but still progress in the Carabao Cup? Or was this a translatable habit that could be established in the new era?

The first signs have been positive for Slot as he aims to win his first silverware. This competition is almost exclusively where Wataru Endo gets time on the field, while Jarell Quansah will have enjoyed playing in his best role for a sustained period.

Liverpool rotated, but was still able to win with relative comfort, though that might not be the case in the semifinals against one of Arsenal, Newcastle United, or the winner of Tottenham and Manchester United.

And as well as resting the likes of Mohamed Salah and Virgil van Dijk, Liverpool was also able to ease two players back into the fold who could be desperately needed in the coming weeks. Harvey Elliott was excellent, while Kostas Tsimikas looked as if he hadn't been away.

Elliott, in particular, will add another dimension to Slot's midfield now he has returned and is back up to speed. Dominik Szoboszlai and Curtis Jones have done well lately but having more options ahead of a very busy period in the season — where the schedule doesn't get any less unrelenting — can only be a major positive.

Even if he is mainly used as a substitute when the bigger games, starting on Sunday at Tottenham, come around, Elliott has proven very adept in that role before. Last season, he made it his specialty.

Given the lack of defensive options that Liverpool has right now, seeing Tsimikas return earlier than anticipated will help as well. Ibrahima Konate and Conor Bradley remain out, but the Reds suddenly look not quite so light of depth. In Elliott and Tsimikas, Slot has extra options. By edging one step closer to Wembley, he has yet another reason to smile.