Arne Slot has admitted Liverpool have struggled to utilise Darwin Núñez’s strengths this season because of problems they encounter against deep-lying defences.

The Uruguay international, Liverpool’s record signing at £85m, has scored four goals and started only 14 of Slot’s 31 matches. Núñez missed Tuesday’s draw at Nottingham Forest through suspension but could feature at Brentford on Saturday with Diogo Jota an injury doubt again.

Núñez’s toils have raised questions over his long-term future. But Slot has backed the 25-year-old to deliver for the Premier League leaders and claimed there is collective responsibility for the striker’s output.

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“Darwin is a striker we have to use in a certain way and we were not able yet to bring the best out of him this season,” said the head coach. “Against Accrington Stanley again you saw he has a lot of pace but, unfortunately for him, most teams sit back a lot against us. I

“If you look back at the goals he scored for us, I remember the one against [Aston] Villa when he went around the goalkeeper on a fast break, that is his main strength – he has other qualities as well – but we are still working on getting him in the best possible positions against a low block. That involves the right timings, the right crosses, the right position to start from and making the right run.”

Slot also believes Núñez has not received sufficient protection from referees this season. The Dutchman, who revealed Jota “felt a niggle” during his 31-minute outing at Forest, said: “The way teams defend our No 9 is something you have to give them credit for. It’s never: ‘Here Darwin, you can score.’ Every time we put in a cross I see a defender all over him. I see it, referees unfortunately don’t.

“For us, in general, it’s more difficult to score against a team like Forest because every time we had a chance they had six, seven, eight, nine or 10 players standing in the 18-yard box. And the one time [Chris] Wood had a chance he was there almost on his own. We weren’t really close to the ball. They only had one chance, we had 15. But with the 15 we had there was always someone close to the ball or all over one of our players. Darwin will score his goals. He already did and he will again.”

A collection of Liverpool supporter groups, meanwhile, have urged the club not to “kill the Kop” by alienating fans through rising ticket prices. Liverpool are to meet fans on Monday to discuss next season’s ticket prices having been criticised for a lack of consultation over last year’s 2% increase.

Before the meeting, Spirit of Shankly, Spion Kop 1906, the Official Liverpool Supporter Clubs’ Network, Liverpool Women Supporters’ Club and cultuRED have written an open letter to the managing director, Andy Hughes, calling for immediate action to reduce ticket prices. It asks that “the club acknowledges and protects the essential role of supporters in sustaining the culture and legacy of Liverpool FC. We do not want prices to kill the Kop or deter passionate, generational supporters from attending matches at Anfield.”