The Liverpool boss admired the youngster's enthusiasm, although he stressed the importance of not going overboard.

Jurgen Klopp says Gary Neville was right to apologise for his comments about Hannibal Mejbri during Manchester United’s 4-0 defeat at Liverpool on Tuesday.

Neville, co-commentating for Sky Sports caused something of a stir when stating that he was “proud” of the teenager for his cameo appearance as a substitute, in which he picked up a yellow card for a late challenge on Reds captain Jordan Henderson and was then lucky to escape a second booking for a foul on Naby Keita.

The former United captain later admitted he had been “unprofessional” in his commentary, though praised the youngster for showing “fight”.

Asked about Neville’s comments, and whether he had any concern that Liverpool’s status as one of the world’s elite teams may lead to other sides targeting them with overly-aggressive challenges, Klopp said: "He had to apologise for that, rightly so. I understand where he is coming from, you want to see some aggression, but there is a difference between aggression and kicking players. That makes no sense. 

“Aggression in football means you are ready to hurt yourself, not the other player. That is aggression in football. 

“I don’t blame the kid [Hannibal], he came on late and the game was quick and obviously wanted to make an impression. He was a bit late here and a bit late there, all good.

Aggression in football is fine but you cannot sort your own problems by hurting the opposition players, that is what I have never understood.”

Klopp added: “I have played 325 professional football games and without aggression and physicality I would have played none! It was my only strength that I had, so I am completely fine with that, but it's about staying respectful, that's all. 

“Things can happen in football, it is a high-speed game but not these kinds of things where you don't care about the other [player]. He is a colleague who wants to play a few days later as well, that's all.”

Speaking about Hannibal’s six-minute cameo, Neville initially said: “To be fair at least the kid's showing something.

"Honestly, it takes a young kid to come on and show the rest of them how to sprint to the ball and put a challenge in. I'm actually proud of him.

Maybe he doesn't like the idea of Liverpool passing around him, I wish the others were the same."

However later, speaking on The Gary Neville podcast alongside former Liverpool defender Jamie Carragher, the 47-year-old said.

“I erred on the slightly unprofessional side of commentary tonight when I said that the kid, I was proud of him because he was going around trying to top people and trying to kick people,” Neville admitted.

But he demonstrated something, he showed something. He didn’t like the idea of Liverpool, at Anfield, passing it around him and the idea of Liverpool taking the mick out of him and his team-mates. At least he demonstrated something. 

“I am not saying it is brilliant because he could have hurt the Liverpool players, but as a Manchester United fan you can respond to that."