Todd Boehly and Mark Walter, who each held a 12.83% stake, have completed the sale of their shares to Clearlake, which previously held a 61.5% majority stake.
Speaking ahead of Friday’s Premier League meeting with Brentford, Alonso acknowledged the significance of the structural change while praising the work carried out during Boehly’s tenure.
The Spaniard was not at Chelsea when the American investors completed their £2.5 billion takeover in 2022 but recognised the challenges involved in stabilising the club after sanctions were imposed on former owner Roman Abramovich.
“I think it is an important day for the club when there is an important change in the structure of the club, new ownership,” Alonso told the media.
“Thanks to the former owners for what they have done. I was not here but I know that they played an important role. And now that Behdad (Eghbali) is taking more control, or almost full control, I think it is good that the main one is clear.
“I have a very good relationship with Behdad; he was the one who came to Madrid to explain the project to convince me and we are working well together.
“As I have mentioned, this is phase one we have completed in project of the squad. It is good and now we move on together.”