Jurgen Klopp has already told Pep Guardiola when he should think about leaving Manchester City.

Speculation around the record-breaking Catalan has been at fever pitch this Christmas, despite him signing a new contract recently, with City and Guardiola himself in unchartered territory. The reigning Premier League champions have won just once in their last 12 games across all competitions.

It's a torrid, and uncharacteristic, run which has seen them slip away from title contention.

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By contrast, modern-day rivals Liverpool are thriving under their new head coach Arne Slot - who replaced Klopp at Anfield this summer - after the popular German stood down from his position in the dugout.

At the time, it was a bombshell call from Klopp as he gave key figures at Liverpool time to pick out a replacement. However, while City extended Guardiola's deal until 2027 last month - and the ex-Barcelona manager has banked a whole heap of credit - there has been increased noise on his position.

That's away from the Etihad Stadium, of course, and Klopp has indirectly advised Guardiola on what to do.

"I love absolutely everything about this club," said Klopp in an emotional statement when calling time on his spell with Liverpool. "I love everything about the city, I love everything about our supporters. I love the team. I love the staff. I love everything."

As and when his goodbye eventually comes, Guardiola's farewell might well be a copy and paste job.

"That I still take this decision, it shows you that I am convinced it's the one I have to take," Klopp went on.

"It is that I am, how can I say this? I am running out of energy and I have no problem now, obviously, I think I know it for already longer that I will have to announce it at one point. But I am absolutely fine now, but I also know that I can't do the job again and again and again."

Guardiola, shortly after penning his contract extension, stressed that he was the man to rebuild City (again) as the club aim to add more silverware to their glittering collection under the 53-year-old. Considering how this term has played out so far, though, the Catalan and City will have to roll their sleeves up.

Energy - the key word in that Klopp send-off - was a running theme for the German and Guardiola as their lengthy rivalry for the game's top prizes provided the subplot for the best part of a decade in the Premier League. When it dilutes, though, even the most exhilarating roles can become taxing.

Keeping that advice from Klopp in mind, only Guardiola will truly know whether or not that's the case.