Liverpool have been dealt another defensive injury blow after Trent Alexander-Arnold was ruled out for a month with a knee problem.

The England international sustained a problem in the warm-up ahead of Saturday’s win at Brighton but played the full 90 minutes and Press Association Sport understands he has tweaked ligaments.

With Joe Gomez still working his way back to fitness after a broken foot and right-back Nathaniel Clyne loaned to Bournemouth earlier this month, it leaves manager Jurgen Klopp short of options.

James Milner appears the likely candidate to start at home to Crystal Palace on Saturday, although fellow midfielder Fabinho – who played centre-back at the weekend because Joel Matip, Joe Gomez and Dejan Lovren are not fully fit – could potentially fill in.

Matip was an unusued substitute against Brighton after recovering from a broken collarbone while Gomez has yet to return to full training.

Youngster Rafael Camacho made his first-team debut at right-back in the FA Cup defeat at Wolves and is likely to be on the bench again.

Fellow academy player Ki-Jana Hoever also made his debut at Wolves, the 16-year-old becoming the third-youngest player in the club’s history, but is unlikely to be considered.

The Holland youth international has endured the highs and lows of football over the last week as he was sent off in the under-23’s Premier League 2 1-1 draw with Brighton a week after making his first-team debut.

At first it appeared the youngster would be booked for a tangle with Aaron Connolly but the intervention of the assistant referee resulted in a red card – something manager Neil Critchley plans to appeal against.

“It was a baffling decision, to say the least,” he told liverpoolfc.com.

“The referee had a yellow card in his hand and had given a free-kick outside the box, which it was – a clear foul and a booking.

“The linesman got involved and changed the decision. That changed the whole complexion of the game. Hopefully we can get that overturned.”

Desite their injury concerns the Premier League leaders still have the best defensive record and Milner singled out goalkeeper Alisson Becker as his player of the season so far.

While centre-back Virgil Van Dijk, currently favourite for the Professional Footballers’ Association Player of the Year award, is receiving rave reviews virtually every week, Alisson has caught Milner’s eye.

The Brazil international, a £65million summer signing from Roma, has kept 13 clean sheets in 22 appearances, conceding just 10 goals in total.

His maiden campaign has not been without its hiccups – with a blunder against Leicester gifting Rachid Ghazzal a goal and a mistake presenting Manchester United’s Jesse Lingard with a simple tap-in – but overall his form has been excellent.

“It’s hard to pick out one player because everyone in the squad has done so well, not just the 11 who are starting,” Milner told Liverpool’s official magazine.

“I think maybe one you could select is Alisson. Coming to a new league is never easy.

“It’s a new lifestyle and you are also getting used to the weather and things like that, but he’s been unbelievable: from how he is around the place, to how good he is on the pitch with his feet and with the saves he makes.

“Every single player makes mistakes and sometimes as a keeper you maybe feel a bit different because mistakes often result in a goal, but if he makes a mistake it doesn’t faze him in the slightest and he remains confident and continues playing as if nothing has happened. That’s so important.

“He’s been unbelievable for us this season so far and I believe that he’ll be a massive, massive player for us going forward.”