At 38, Cahill is now enjoying retirement but this summer he has been back in the States with the Blues as one of our ambassadors.

So we sat down with the former England defender to find out why pre-season is so important to both the coaching staff and the players.

Cahill explained: ‘Pre-season helps you sharpen the tools and get back to the level of fitness you need to be at. It is not just about pure fitness, it is about things like getting your eye back in.

‘The lads nowadays, especially the ones playing at international level, you don’t get much time off over the summer so you don’t lose a huge amount of fitness over three weeks off but what I used to lose was that sharpness. The on-pitch decision-making and things like that.

‘Then if you have a new manager, it is about trying to adapt to a new style of play. So two things really; working on your team shape and then trying to get back up to speed in time for the start of the season.’

Cahill has seen his fair share of new managers during his career so he knows firsthand why pre-season can be so important.

This summer saw the Blues appoint Enzo Maresca as our new head coach and just one month into his reign, you can already see signs of the work he has been doing with the players on the training ground coming to fruition.

Maresca has continually stressed he is not overly focused on results at this stage, instead, he wants to see evidence of the players implementing his distinctive style in training and matches.

Sloppy goals, conceded in quick succession in either half, meant the Blues lost their last pre-season friendly against Manchester City 4-, following an impressive showing in the 3-0 win over Club America, but Maresca’s men enjoyed more possession and created just as many chances against the reigning Premier League champions at Ohio Stadium.

There has been steady progression in recent weeks as the new staff and new signings such as Filip Jorgensen, Tosin Adarabioyo, Renato Veiga, Kiernan Dewsbury-Hall and Marc Guiu all get to know their new team-mates.

And Cahill said: ‘Pre-season is a chance for the head coach to work with the whole group at once to get his ideas across. There is a lot he can gain from pre-season and it gives him a chance to get to know the players as well. It is a big part of the season.

‘Pre-season is a great time for the new signings too because they can integrate with the squad. You are spending all day together at the hotel so it is a great time to have the squad all together.

‘Likewise, with the new head coach and all of his staff, it is a chance for them to pass on everything they want to ahead of the new season.’

With new staff and players arriving this summer, the tour to the USA also provides the squad with a great opportunity to build a sense of togetherness.

Whether it is going out for team meals or simply playing table tennis and darts after training, the Blues players have spent most of the last two weeks together and the players have already spoken about how much the five-game trip is helping build unity.

That is something Cahill expanded on, adding: ‘You are spending every day together for two and a half weeks, so you have to work really hard on the training ground and then when you get the odd evening off, it is a chance to maybe go for a meal together or walk around town together and it all helps integrate the squad.

‘Young players sometimes come on tour who you maybe don’t know personally and you usually have some new signings so it is an important time of the season.’

Chelsea have already played in Santa Clara, Notre Dame, Atlanta and Ohio during their USA tour and on Tuesday they will conclude the visit Stateside against the reigning Champions League holders Real Madrid at the Bank of America Stadium in Charlotte.

Cahill arrived midway through the tour, with Carlo Cudicini out with the Blues for the first week, and both men have been mingling with supporters on a daily basis and helping to put on coaching sessions out in the community.

These pre-season tours are a special time for players and fans alike, with Cahill saying: ‘I used to love coming to the USA for tours. It is a great atmosphere and I feel like everyone comes out for a good time.

‘Chelsea have a huge following in America and it is their chance to see the players in person, as they don’t usually have the chance to.

‘The facilities here are second to none so it is easy for the players to adapt. You have the on-pitch work but also the gym work and other elements so the facilities here really help with all that.

‘I used to love coming to the USA as a player.’