Wayne Rooney calls for Arne Slot to drop £125m man Alexander Isak - as Man United legend highlights the key issue that has plagued striker since British record transfer to Anfield

Liverpool manager Arne Slot should drop British record signing Alexander Isak, Wayne Rooney has claimed after Manchester United's shock 2-1 win at Anfield.

The reigning Premier League champions suffered more disappointment on Sunday with a fourth successive defeat in all competitions, losing at the hands of their bitter Manchester rivals.

Harry Maguire's 84th-minute header handed the Red Devils their first win at Anfield in over a decade, after Liverpool forward Cody Gakpo cancelled out Bryan Mbeumo's early strike for United 62 seconds into the match.

Isak, who joined Liverpool for a record-breaking fee of £125m last summer after forcing a move from Newcastle, made his third successive Premier League start for the Reds on Sunday but continued to struggle in front of goal.

The Swedish international has yet to score a league goal for Liverpool despite netting in the Carabao Cup, chalking up just two goal contributions in seven appearances across all competitions so far.

Meanwhile, fellow summer arrival Hugo Ekitike, who joined for £79m from Eintracht Frankfurt, enjoyed a blistering start to his Liverpool career with three goals and an assist from his opening five Premier League matches, before being replaced by Isak.

And Manchester United legend Rooney has now called for Slot to drop the Swede, insisting he is struggling because he has not had a full preseason.

Before pushing through his dramatic Deadline Day transfer to Anfield, Isak refused to train at Newcastle before eventually building up fitness individually away from Eddie Howe's core group.

'I wouldn't play Isak, he hasn't looked ready since coming from Newcastle,' Rooney said on The Wayne Rooney Show.

'He hasn't trained, hasn't had a pre-season. It's so important. While Newcastle were training he was probably sat at home on the phone to his agent for six hours a day trying to get a move.

'It's so difficult when you don't have a pre-season. He might've done stuff by himself but he's paying the price of it. On performances, he doesn't deserve to be playing ahead of Ekitike.'

Slot enjoyed a superb debut season at Liverpool last campaign, winning the Premier League in the wake of Jurgen Klopp's emotional exit from Anfield after nine fruitful years at the helm.

Despite splashing out almost £450m on new stars including Isak, Florian Wirtz, Milos Kerez and Jeremie Frimpong, the Reds have mostly looked disjointed and lacked fluidity during the early part of the season, losing three of their opening nine league games.

By no means out of the title race yet, currently sitting just four points behind league leaders Arsenal in third, there is plenty for Slot to sort out if Liverpool are to win back-to-back titles come the end of the season.

Rooney believes complacency is hurting the reigning champions — and that Slot is beginning to buckle under pressure.

'They've got a bit complacent,' Rooney added.

'For Arne Slot, you forget because he won the Premier League, but he's still quite young - 47 years of age and this was the first time he's lost four in a row in his career.

'[Against Manchester United] he was arguing with the officials on the touchline, I haven't seen that before from him.

'We're starting to see things unfold which shows that there's pressure there.'