Liverpool stars should perhaps be wary of boss Jurgen Klopp amid their current slump as it is claimed he once slapped a player across the face during his time at Borussia Dortmund.
The reigning champions are going through a considerable rough patch of late, picking up just three points from a possible 15 in their last five Premier League games.
Thursday's defeat against Burnley was particularly disappointing for Klopp, who described the end of their 68-match unbeaten league run at Anfield as a "massive punch in the face".
Asked about how he would get the belief back into his players after the match, Klopp replied: "It's the job a manager or a coach has to do."
He added: "We can do more with this group, we can play much better football, that is my concern."
How Klopp does that is now down to him, but he has been known to resort to unorthodox methods in the past.
Serbian defender Neven Subotic played under Klopp for the entirety of his seven-year stint as manager at Dortmund.
Despite achieving great success at the club, there were times when things were not going quite as well on the field.
As Subotic recalled to The Athletic : "When you get the feeling as a player that you’ve already achieved something, that you have a bit of experience, you suddenly don’t want to say ‘yes’ to everything any more.
"I guess that’s human nature. If it was necessary, Klopp upped the volume. He shook us up a bit, to wake us up.
"Not by saying: ‘You have to play something different, boys, it’ll be tough’. No, he went up to a player and slapped him across the face. You think: ‘Oh, he might slap him back’.”
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Liverpool are now under pressure to get back to winning ways quickly, and face two tough away trips ahead of them starting with Man Utd in the FA Cup, followed by Tottenham in the league.
Asked whether Sunday's fourth round tie at Old Trafford gives his side an opportunity of a break from their dismal league form, Klopp said: "Yeah, it’s a different competition.
"Again, we want to go through and for that we have to play really well because United is obviously in a good moment and they get all the results they wanted so far.
"That’s why we have to be ready, 100 per cent."
