We all have that one jovial friend who, when his/her patience eventually runs out, you know that the shit has hit the fan.
Jurgen Klopp is one of the most affable managers in the Premier League but he was understandably not in his usual top form following Liverpool's 2-2 draw at Sunderland.
Twice Liverpool led, thanks to goals from Daniel Sturridge and Sadio Mane, but on both occasions they were pegged back thanks to Jermain Defoe penalties.
And in his post-match interview, Klopp was a vision of bottled up fury as he criticised the hectic festive fixture list that saw the Reds play two games in less than 48 hours.
The Reds boss stopped short of losing his temper but was visibly agitated as he apologised to the interviewer for his mood because, to be fair, he's always a class act.
https://www.youtube.com/watch?v=R9lpjdGfKGo
But it was one of the few times that we've seen the German speak to the media without at least one smile appearing.
One of the game's incidents that most vexed Klopp was the build-up to the awarding of Sunderland's second penalty.
"For sure, I saw a second ago, that there was no foul for the second free kick and then penalty. It was no foul," Klopp said.
"It's very difficult today because I usually speak about football but I have no idea what my players are capable of or not."
When asked for clarity on his stance, Klopp responded, stony-faced, with a no-nonsense "it was no free kick!"
You wouldn't like him when he's angry.
