LIVERPOOL, England (AP) — Xabi Alonso said he had “no time for tourism” before returning to Liverpool as Bayer Leverkusen coach, but he expected a happy homecoming, a 4-0 defeat and humiliation at the hands of Der Man claiming the job many wanted from him was probably the last thing he expected.

“Painful,” Alonso described his evening. That was a bit of an understatement. Liverpool fans sang Alonso’s name at the end of the game, but not before serenading Arne Slot, the coach who has made a stunning start to the club’s coaching life as Jurgen Klopp’s successor.

Alonso secured his status as a Liverpool legend by helping Rafael Benitez’s side to UEFA Champions League success in 2005. The overwhelming majority of fans chose Alonso to replace Klopp when it was announced the German would be leaving at the end of last season.

Alonso’s decision to entrust his future to Leverkusen, who were on their way to their first ever Bundesliga title, was initially met with disappointment from Liverpool fans. However, the club already had their sights set on Slot, the then Feyenoord coach, and it was the 46-year-old who was chosen to fill the void left by Klopp.

Six months later, Liverpool are top of the Premier League and Champions League and Slot is the new favorite of the Anfield crowd. Nobody is talking about Alonso anymore and after this clear victory the debate is officially over.

Slot has made a name for himself and his Liverpool are threatening to dominate England and Europe this season. Alonso, on the other hand, has struggled to maintain Leverkusen’s incredible form from last season, when they won the Bundesliga without defeat. It’s now two wins from eight games and the magic he showed not long ago is now gone. He is still a rising star in the coaching world but Alonso was put to school by Slot at Anfield and it was a brutal lesson for the 42-year-old.

A second-half hat-trick from Luis Díaz and a header from Cody Gakpo sealed Liverpool’s victory after a cagey first half ended goalless. But just like they did against Brighton and Hove Albion in the Premier League at the weekend, Slot’s team shifted gears after the break to overwhelm their opponents.

Díaz was central, scoring his first hat-trick for Liverpool while playing in an unfamiliar centre-forward role. The Colombia international’s first goal – a great chip over goalkeeper Lukas Hradecky after a great pass from Curtis Jones – was the highlight of his hat-trick.

If you analyze the changes Slot has made since replacing Klopp, they are more subtle than significant. The players are the same and not much happens without Mohamed Salah making an impact up front or Virgil van Dijk in defense. But is it the same as it ever was? Not quite.

Slots Liverpool are more solid at the back than Klopp’s team, the full-backs have fewer attacking runs, and against Leverkusen midfielder Ryan Gravenberch sometimes played so deep that he took on the role of a third central defender. He was also given the task of accompanying Leverkusen playmaker Florian Wirtz in order to destroy the creative focus of Alonso’s team.

Speaking to reporters after the game, Slot said he was surprised by Alonso’s line-up and the decision to use striker Victor Boniface in the wing position.

“Leverkusen played without the number 9 and I have never seen Boniface play from the left,” he said, admitting it took until the second half for his players to click.

“In the second half we adjusted the game plan and took more risks.”

And that seems to be the key to Slots Liverpool. They play one way in the first half before upping the ante in the second half. Klopp’s Liverpool were on top of their game for 90 minutes and it brought success and excitement to Anfield, but Slot finds another way and it was good enough to dismantle the German champions.

“The result is painful, the performance is even more painful,” said Alonso. “It can happen that you come to Anfield and lose. Losing 4-0 is not nice.”

“They are a top team and punished us. It was a shame that we couldn’t keep it 1-0 for 15 to 20 minutes. They did it against Brighton, they did it against us.”

“To be a top team, we have to go through these difficult moments – suffer in moments that are not so nice, especially in the Champions League. That can happen in this competition.”

Leverkusen and Alonso are not Champions League newcomers, but they looked like it in the second half. And that is perhaps the greatest tribute to Slot and Liverpool. They made an impressive team look ordinary.

When Real Madrid visit Anfield on Matchday 5 later this month, they would do well to heed the warning.