Liverpool head coach Arne Slot has labeled Trent Alexander-Arnold the "best player in the world" when he is in wide positions — but says he made it clear to the Reds' number 66 at the start of the season that his defending needed to improve.

Alexander-Arnold has generally looked much better in a defensive sense this season, playing a more straightforward role in the team than his inverted position under Jurgen Klopp. But he was criticized heavily by Roy Keane at the start of 2025 for his poor showing in the 2-2 draw with Manchester United.

"Trent is the best player in the world when he is down the line. His crosses are incredible," Slot told TNT Sports. "He is good centrally — we saw this with the England team — but he’s special on the side."

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Slot has tended to keep Alexander-Arnold in a wide berth as a result. He has fewer assists than when he was at his marauding peak but played a key role in Darwin Nunez's match-winner against Brentford at the weekend that led to Liverpool being six points clear at the top of the Premier League table.

"When we started to work together, I emphasized also a bit on his defensive work," Slot continued. "He had to keep producing the numbers in assisting goals, but if we wanted to be a team that concedes less shots, he had to improve a bit in defending.

"I have shown him that he’s able to do so if he puts enough effort in. Sometimes, like the [Manchester] United game, which was an exception this season, he seems to lack a bit of effort in some moments. But if he’s at the top of his game, he’s a very good defender as well."

Keane said that Alexander-Arnold was likelier to be playing for Tranmere Rovers next season than Real Madrid after Bruno Fernandes got the better of him at Anfield. But Slot believes that he is getting better out of possession.

"We have spoken a lot to him about consistency," the Dutchman continued. "Because he’s been quite long with this club, he sometimes trains or has played games like, 'Ah, it’s another one from 200 that I’ve already played or all these sessions I’ve already had'. This is where we’ve worked on, and I think we can see the progression he has made."

Liverpool.com says: Alexander-Arnold has definitely improved this season but the Manchester United game was so bad (and in such a high-profile moment) that it will be referenced for some time. Ultimately, you don't win the Premier League and the Champions League by being a liability; his weakness has always been greatly exaggerated.