The Reds continued their upward trajectory into 2024 with a resounding victory at the Emirates to secure a spot in the fourth round.
Despite enduring periods of pressure from Arsenal, Liverpool capitalised on their opponent's missed opportunities, securing victory via a Jakub Kiwior own goal and an added-time strike from Luis Diaz.
Klopp, praising his team's performance, particularly highlighted the versatility of the Englishman.
"What a game he played by the way in all the positions he played,” Klopp said.
The Scouser started the match at right-back, frequently coming inside, before switching to play as the lone 'six' during the final 15 minutes after both Alexis Mac Allister and Curtis Jones were withdrawn.
It was during this time that his inswinging free-kick got a flick off Kiwior to take it past Gunners keeper Aaron Ramsdale.
"You see his class on the ball," Klopp added.
Endo absence felt
Despite a difficult start to life on Merseyside, with Wataru Endo now away on international duty, Liverpool are going to have a tough time replacing the Japan international.
Alexis Mac Allister’s return to fitness is very timely: the Argentinian started the game and showed some excellent touches and neat passing, but his usual shortcomings as the deepest-lying of the midfield trio beame apparent when he was bundled off the ball by Declan Rice in the 29th minute, presenting Kai Havertz with a chance.
Curtis Jones then took over in that position when the Argentinian was hooked after an hour, but when he too was withdrawn, it was Alexander-Arnold who filled in there, giving him the freedom to dictate the play.
With Mac Allister still coming back from injury, we can likely expect this type of rotation to continue - and Alexander-Arnold's versatility to really be used.