Mikel Arteta learned his trade as Pep Guardiola's right-hand man. Now it's Pep's turn to take a leaf out of his old apprentice's book - by learning what not to do.
Two years ago, Arteta attempted his boldest gamble yet by insisting he had "no number ones", constantly rotating between the confused Aaron Ramsdale and David Raya. Guardiola can't be as brazen.
Every save, flap and dodgy pass came under intense scrutiny as Arteta's experiment snowballed into a crisis. The uncertainty rocked the whole defence in the early part of the season and ultimately led to the Gunners finishing two points behind Guardiola's title winners.
City could be walking into the same trap with a deal for Gianluigi Donnarumma in the works. It would mean the most promising goalkeeper of his generation would spend the year leading up to a World Cup sitting on the bench, twiddling his thumbs.
James Trafford, 22, thought he would have been usurping Ederson after rejoining from Burnley this summer. Instead, he'll be playing second fiddle to new boy Gianluigi Donnarumma - who is only four years older.
Donnarumma isn't a short-term fix, he's the long-term solution. And Guardiola can't give one second of thought about rotating between the two.
Terrifying Rees-Zammit
LOUIS Rees-Zammit is back and rugby should be terrified. US sports push athletes to a different stratosphere.
Even though his spell in the NFL was unsuccessful, those 18 months training with the world's best will have taken him to a level never seen before in domestic UK rugby.
And he will be the man to drag Wales out of their current rut.
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