Roy Keane suggested Trent Alexander-Arnold should be moving to Tranmere rather than Real Madrid after criticising the Liverpool player's "schoolboy defending".
Alexander-Arnold has been linked with a switch to the Spanish giants during the transfer window, but Keane was distinctly unimpressed with his performance in the first half of Sunday's game against Manchester United.
Analysing the chances which Amad Diallo and Rasmus Hojlund failed to convert at Anfield during half-time, Keane said on Sky Sports: "It's too easy.
"Them chances for United [come from] 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, the way he's defending he's going to Tranmere Rovers after this. He's got to do better."
During a debate with Jamie Carragher, Daniel Sturridge and Gary Neville about Alexander-Arnold, Keane said that the player should join Real Madrid.
"I think he's got to go for it," said Keane.
"It's not as if he's played 50 games, he's played hundreds of games for Liverpool. Jamie is on about them being the best team in the league, they might be the best team at this moment in time but it's not as if they've won loads of titles.
"If Liverpool have dragged their heels with contracts, it's called a bit of self-worth, if a club comes in for you like Real Madrid, then I'd say for the lad, go for it. It's a short career."
Keane said Manchester United's performance was a "surprise" to him.
"The argument about all of this stuff is do it in the other games," he said.
"They done it at City recently. You can't just pick and choose when you want to turn up for Man United and have passion.
"I don't think anyone would have predicted Man Utd scoring two goals today and nearly winning it at the end. Liverpool had their chances. I'll take my hat off to United today, they showed a bit of passion, lots of quality, a bit of fight and showed what playing for Man United is all about. The key is they've got to back it up."