Roy Keane criticised Trent Alexander-Arnold’s ‘schoolboy’ defending against Manchester United on Sunday.

The Liverpool right-back endured a difficult opening 45 minutes at Anfield with the majority of the opposition’s attacks coming down Alexander-Arnold’s flank. In particular, United captilized on his slack defending as Rasmus Hojlund saw a first-half effort saved by Alisson after Alexander-Arnold failed to track back, while early in the second period a similar incident resulted in Virgil van Dijk blocking Diogo Dalot’s goalbound strike.

Lisandro Martinez’s goal in the 52nd minute also came down the Liverpool right, with Gary Neville claiming during the game that Liverpool’s right-back was ‘struggling’. His former United team-mate was in agreement and jokingly claimed Liverpool’s no.66 won’t continue to attract interest from Real Madrid with performances like that.

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“Trent defensively has been all over the place,” Keane said during Sky Sports’ half-time coverage. "It's too easy for them [United] with those chances, a couple of balls over the top.

"We talk about how brilliant Trent is going forward, but Trent's defending today, my goodness, it's like schoolboy stuff. There's talk about him going to Real Madrid, he's going to Tranmere Rovers after this."

Alexander-Arnold is a transfer target for Real, who saw a January bid turned down earlier this week. Reports have claimed the European champions lodged an offer of £20m ($25m) which was rejected as Liverpool will not consider selling him midseason. Contract negotiations continue over a possible extension.

The England international’s current deal expires at the end of the season and he could be available for free if a fresh deal cannot be agreed. The Mirror claimed the Reds have offered Alexander-Arnold a deal worth £78m ($97m) over five years.

Virgil van Dijk and Mohamed Salah’s contracts also expire this summer, but there is more confidence that an extension will be agreed between the club and the pair.

Liverpool fans made their view clear at Anfield on Sunday as a banner was held up stating: “FSG give Mo and Co their Do.” The Reds typically do not offer similar wages to the likes of Real Madrid and Manchester City.