A young Manchester United fan who made a bid to stop Liverpool winning the title has been left shocked after Jurgen Klopp sent him a personal reply.
Daragh Curley, from County Donegal, wrote to the Liverpool boss for a school assignment.
The 10-year-old asked if it would be possible for Liverpool to lose some games so they would not win the league.
Klopp said the letter had been "cheeky" and he had written the response privately.
"I cannot answer all the letters, I get a lot," said Klopp, speaking at a press conference on Friday.
"But it was nice, it was cheeky. We had time that day so I read the letter and I replied.
"It's a private thing, I get a letter, I respond and the next day it's in a newspaper - I don't like that too much but it's all fine.
"I like working for Liverpool and I like the rivalry we have," he added.
"But I love even more if we can keep that (rivalry) on the pitch. But apart from that they can be happy and we should be happy and I hope Daragh is now happy - he looked like it on the picture I saw later, so good."
In the letter, Klopp praised Daragh's passion, but explaining Liverpool could not drop points on his behalf.
Daragh's dad Gordon told BBC News NI that while most of his classmates were writing fan letters, Daragh instead decided to write a letter of complaint to the Liverpool boss.
In the letter, the Glenswilly National School pupil wrote: "Liverpool are winning too many games. If you win nine more games then you have the best unbeaten run in English football. Being a United fan that is very sad.
"So the next time Liverpool play, please make them lose. You should just let the other team score. I hope I have convinced you to not win the league or any other match ever again."
Mr Curley said he was shocked when a reply came.
"My wife Tricia was up in the local post office/shop and she was told that there was a registered letter there for Daragh Curley," he said.
"She was wondering who would be sending Daragh a registered letter, but when she mentioned it to Daragh he said 'oh it's Jurgen Klopp'.
"And it actually was Jurgen Klopp."
Klopp's Liverpool are on course to win the Premier League and have not lost a league fixture so far this season.
In his letter to Daragh, he said: "Unfortunately, on this occasion I cannot grant your request, not through choice anyway.
"As much as you want Liverpool to lose it is my job to do everything that I can to help Liverpool to win as there are millions of people around the world who want that to happen, so I really do not want to let them down."
"Luckily for you, we have lost games in the past and we will lose games in the future because that is football.
"The problem is when you are 10 years old you think that things will always be as they are now but if there is one thing I can tell you as 52 years old it is that this most definitely isn't the case."
He added that Manchester United were lucky to have Daragh as a fan and praised his passion for football and for his club.
Mr Curley said that Klopp "seems to be an awful, awful decent individual".
"I would be a Man Utd fan myself, it's grating that Liverpool are doing so well, but behind it all you have to respect Klopp and what he's done," Mr Curley said.
"He came across as a nice guy all along, I suppose this letter really confirms to me that he is a decent, decent guy.
"What I love about the letter is that it's about sportsmanship and respect too and I think saying that to a 10-year-old is great."
However, Mr Curley said his admiration for Klopp would not cause either himself or Daragh to switch their allegiances.
"There's reinforcement techniques ongoing just to ensure that there's no swaying from the Man Utd mandate," he said.