The definition of a good preseason is different things to different managers and in a summer where we have had a Copa America, Olympics and European Championship, this one has been a tough one to gauge for many.

So many players are yet to feature following international duty and in the case of Chelsea boss Enzo Maresca and Liverpool’s new head coach Arne Slot, they have yet to even meet several of their first team stars.

So, what have we learnt from the sides who travelled to the US to fulfill both footballing and marketing duties?

City stars shine bright for future

For Manchester City they may have started slowly but they ended the tour in very familiar fashion, with a hat-trick from Erling Haaland helping his side to a 4-2 win over Chelsea.

The two sides are likely to be somewhat different when they meet in the opening game of the Premier League season but one thing that is certain is that future is definitely bright for City.

As well as the likes of Rico Lewis, James McAtee, Oscar Bobb and Joshua Wilson-Esbrand we also saw Jahmai Simpson-Pusey, Joel Ndala, Jaden Heskey, Jacob Wright, Mahamadou Susoho and Micah Hamilton getting valuable minutes for Pep Guardiola's side.

“We have two or three [Academy players ready for senior football],” said Guardiola.

“The experience [they gained], they played against the Chelsea team or Barcelona, it’s an unbelievable experience for them.”

Arsenal add to depth early on

After being pipped to the Premier League title last time around Arsenal boss Mikel Arteta will have more options at his disposal this time around.

He acted quickly to add to his defensive options with the signing of Riccardo Calafiori from Bologna, who he said will suit their more “evolved” style of play.

But another player who could make a huge difference is Jurrien Timber, who has managed just three appearances since he arrived 12 months ago.

The Gunners paid Ajax £38m for the Netherlands defender but he missed almost the entire season with injury but he has impressed in Arteta’s side in the US. Oleksandr Zinchenko, who could be the man Timber replaces, described the 23-year-old as “unbelievable”. His and Calafiori’s versatilty across the backline could be key to the “evolved” style Arteta is promising for the forthcoming season.

New Liverpool style bodes well for Slot

Liverpool are another team we expect to look very different during this campaign, following the departure of Jurgen Klopp after nine years at the club.

Arne Slot, who arrived from Feyenoord got off to a flying start and ended the US tour with a 100% record which included wins over Arsenal and Manchester United.

The style of play has been described as an "elegant", typically Dutch style, by midfielder Harvey Elliott who has impressed in preseason.

Darwin Nunez, Alexis Mac Allister, Diaz, Alisson Becker, Joe Gomez, Alexander-Arnold, Cody Gakpo and Virgil van Dijk have all yet to meet the manager so how that team looks once you add these key players in is anyone’s guess.

Chelsea transition a tough ask

Chelsea are another team going through a transition following the arrival of a new boss. Enzo Maresca replaced Mauricio Pochettino at Stamford Bridge, after guiding Leicester back to the top flight.

Maresca is known for possession-based style of play and after telling Conor Gallagher he didn’t fit his style and would not be a regular starter, the England international has agreed a move to Atletico Madrid.

The new coach is looking to install playing out from the back as one of his core principles at Stamford Bridge, but there is still work to do, after they were caught out twice against City, who took advantage of mistakes by Tosin Adarabioyo and Moises Caicedo.

It will be interesting to see how many of Poccettino’s regular starters can force their way into this new-look Chelsea squad.

The Blues have also added Adarabioyo, Omari Kellyman, Marc Guiu, Kiernan Dewsbury-Hall, Renato Veiga to their first-team squad, which now boasts 45 players.

Injury issues arise again for United

For Manchester United, their preseason tour was dominated by more injury problems.

After enduring 66 different injuries last season Erik ten Hag will have been hoping for a change of luck, only to see new signing Leny Yoro ruled out for three months and Rasmus Hojlund also set for six weeks out.

This news came on top of having to chop and change their defence over concerns around the fitness of Jonny Evans, Harry Maguire and Victor Lindelof. Add to that the impending departure of Aaron Wan-Bissaka and United’s lack of depth at the back has been highlighted once more.

That’s not their only worrying position though, with question marks remaining over the form and future of Casimero, who has started every game so far.