Jurgen Klopp has told Marko Grujic that he needs to channel his aggression better in order to fulfil his full potential at Liverpool.

The 21-year-old Serbian midfielder was criticised by Crystal Palace boss Frank de Boer for a crude challenge on Wilfried Zaha during last week’s Premier League Asia Trophy in Hong Kong.

Grujic was booked and ended up getting a final warning from referee Bobby Madley following another foul.

Klopp has great hopes for the combative £5.1million signing from Red Star Belgrade, who looks ready to kick on after an injury-plagued first year with the Reds.

However, the manager says he needs to make some important adjustments to his game.

(Image: Stanley Chou/Getty Images)

“I didn’t see it properly at the time but I heard it could have been a red card (for the foul on Zaha),” Klopp told the ECHO.

“That’s not good. For Marko, it’s something that he has to change.

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“He’s a fantastic player, a really skilled boy. Tall, quick, talented footballing wise, all good.

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“But in these defensive situations, you always need to be early enough there so you are close enough to make a challenge and not a foul.

“I said it to the players after a session when we had a little situation with Divock (Origi) and Trent (Alexander-Arnold).

“It’s about coming too late, switching off the machine, trying to sort a situation in which you were late in mind. I hate that.

“When that happens you need to run, not foul. Make more steps, go, go, go. For me it’s always a bit lazy.”

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