Ross Barkley remembers a Sunday afternoon at Goodison Park a little over two years ago. He was still at Everton then, playing under the guidance of Ronald Koeman in the Dutchman's first season at the club.

The man stood in the away dugout was also experiencing his maiden campaign with a new team. He had just watched on as Barkley set up two goals in a 4-0 victory for Everton. That team was Manchester City and that manager was Pep Guardiola.

Not only was that result the heaviest of his career, it also put Man City 10 points behind leaders Chelsea and left them outside the top four.

Ross Barkley has pointed to early criticism of Pep Guardiola, as Maurizio Sarri struggles

It was January, and Pep had already been rechristened Fraudiola, the Bald Fraud. This so-called genius of Barcelona and Bayern Munich was, clearly, unable to hack it in the Premier League.

Barkley recalls this memory in response to a question about the turbulence being endured at his current club Chelsea under the stewardship of Maurizio Sarri.

Another manager, previously hailed as a genius, this time with a philosophy on football so unique it is named after him, struggling to implement his 'Sarri-ball' in his first season in the Premier League.

Three league defeats in four, including a 4-0 drubbing at Bournemouth and 6-0 to Man City, who Chelsea play again today in the Carabao Cup final.

Barkley's point is clear: look at Man City then. Look at them now. Sarri, despite the recent troubles, has actually won a game more after his first 43 matches in charge of Chelsea than Guardiola managed in the same period.

The Italian appears to be on borrowed time following a poor run of results with the Blues

'We're learning every day,' says Barkley. 'We are all top-class players and we all want to learn more. If you compare Pep Guardiola's first season, they went through a bit of an up-and-down spell. When I was at Everton, we beat them 4-0.

'We have got ambition to be one of the best footballing sides in the world. We're one of the biggest clubs in the world.

'The style of play the manager wants is not where it is at now. Over time it will come. Bad days don't always stay. Good times are ahead. We are doing it every day in training. I am sure, with time, you will see how good it will be.'

There does seem more to it, though. Guardiola rigidly stuck to his principles in his first season but learned to adapt, to the benefit of Man City's trophy cabinet.

Sarri will not budge. He will not play N'Golo Kante in his best position. He will stick with Jorginho regardless of effect and continues to criticise his players in public, saying they are difficult to motivate.

Chelsea defender Antonio Rudiger even described Sarri's long tactical sessions, even on the day of a game, as like being back at school.

Barkley has experience of beating a Guardiola City side, when the Spaniard was scrutinised

'Every manager has their own way of approaching games,' says Barkley. 'We did similar things at Everton under Roberto Martinez. It's just a way of being organised in a game. It's only going to help us. Personally, I don't mind it.

'He tries to improve every player. Throughout his career, you can see at Napoli how well he did with the players he had, how much he improved them. We went through a bit of an up-and-down spell in the last couple of weeks, but we're confident we'll come through it and achieve success.'

How is that success defined? For Sarri right now, it might just be surviving in the job for another week. The Italian is said to be close to the sack under an owner in Roman Abramovich famous for having the twitchiest of fingers.

'Over the years – me not being at the club – you see managers come, managers go,' said Barkley. 'It's all about success, winning trophies. That's why I came to the club. If things aren't going well there's always going to be pressure that comes with it.'

His manager has a different view of success. Sarri says he does not judge it on silverware. Perhaps that's because he's never won a trophy, with his only previous final this season's Community Shield in which he suffered defeat, once again, to today's opponents Man City.

'It depends on the club,' said Sarri. 'If I am, for 20 years, the coach of a very small team and I am able to stay for 20 years in the Premier League, probably I am a top coach. So it depends on the club. It's easier to win a Champions League with Real Madrid than with Borussia Dortmund.' It is unlikely Abramovich also sees it that way.