Arne Slot has said Alexander Isak is ready to showcase the qualities that made him Britain’s most expensive footballer.

Isak’s low-key start to life at Liverpool has been attributed to him missing the majority of pre-season training with Newcastle while he forced through a record £125m transfer to Anfield. Seven weeks after joining the Premier League champions, however, and having played the entirety of Sweden’s two recent World Cup qualifiers, Slot believes match fitness is no longer an issue for a striker who aims to kickstart his Liverpool career against Manchester United on Sunday.

“Fitness-wise he is close to the level he should be and we can judge him in a fair way from now on,” said the Liverpool head coach.

“The first five or six weeks, of course we had the player we signed but he was not completely ready. He was getting fitter but he had to do this in a Premier League game. This is not normal for a player. Ideally you would use him earlier in friendly matches but there is no time in the middle of the season for a friendly so we had to build him up playing Premier League and Champions League...