The Kop sang Slot's name towards the end of the 4-0 rout on Tuesday night.
He later acknowledged: "It's always better for a manager that this happens than when they start to boo! It's special. It was special from the start and, therefore, I think I have to thank Jürgen (Klopp) because he was the one who came up with the song. It is always special if you are a player if they sing for you.
"Some players get used to this – I didn't, they only sung a few times for me in my playing career. That's what you see a bit more people singing for a manager is not that common, at least not in Holland but maybe here it happens a lot.
"So, it was nice to hear today, but I also like it a lot that after that they sang for Xabi as well because he was so special for this club, so he deserves it for this, but also his achievements at Leverkusen – champions last year, won the cup, played a final in Europe. For all these reasons, he deserved the fans to sing for him as well."