However, Alonso predominantly deployed a 4-2-3-1 formation, albeit it was fluid.
Speaking after the win over the Rossoneri, he said: "We want to be versatile in our approach and system.
"The principles are the same but the movements can change; we need to be unpredictable, we want to be flexible, and we want to have a threat.
The system is just a picture; you need to move, rotate and create dynamics [in the team] and that is when the picture becomes a movie.
"We are not just sticking to one idea and the more options that we have, the better team we will be."
So much of the positivity around Stamford Bridge on the eve of the new season stems from the fact that Alonso is now in the dugout - one of the most highly-regarded young coaches on the planet, regardless of his short-lived spell at Real Madrid last season.
The man who ended Bayer Leverkusen's long, long wait for a Bundesliga title in 2023-24, going unbeaten in the process and implementing a front-footed, attacking brand of football, there is a genuine hope that Alonso will swiftly transform Chelsea into title challengers, and his status as manager rather than head coach means he is already having a significant say in business operations behind the scenes.
It will be very interesting to see how the Spanish tactician sets his team up; he had unprecedented success with a back-three system at Leverkusen and Chelsea's two most convincing performances of pre-season, against Milan and Real Sociedad, came playing in that shape. Interestingly, new arrivals Palestra and Quenda are comfortable operating as wing-backs.
However, Alonso predominantly deployed a 4-2-3-1 formation, albeit it was fluid. The 44-year-old has insisted that he wants tactical flexibility. Speaking after the win over the Rossoneri, he said: "We want to be versatile in our approach and system. I think we have the players to adapt to different ones.
"The principles are the same but the movements can change; we need to be unpredictable, we want to be flexible, and we want to have a threat. The system is just a picture; you need to move, rotate and create dynamics [in the team] and that is when the picture becomes a movie.
"We are not just sticking to one idea and the more options that we have, the better team we will be."
