Terry noted that the long-term contract signifies Alonso will be fully in charge of recruitment during a crucial summer transfer window.
"He's coming in as the next Chelsea manager, and that's the key to it," Terry said.
He explained that Alonso brings fresh tactical ideas, including his preferred 3-4-3 formation, to a young squad that gained valuable Premier League exposure during a difficult season.
"He's been named the manager of our football club.
So that tells me from the outside that he's going to be the man fully in charge, he's going to be in charge of all signings, and I think the responsibility of managers when they do that and the connections he'll have, as an ex-player and someone who's played at the very top, he's had a very short managerial career, but been very experienced and been very successful early on in that as well," Terry shared.
Terry expressed confidence in Alonso's ability to captivate the dressing room through his communication style and football philosophy.
He remains optimistic about the club's trajectory under the new leadership.
"So, comes into the building with a fresh idea of how he wants to play with Chelsea for sure, and even though it's been a really poor season for us, I think our younger players that we've had and the exposure they've had to the Premier League this year will be better for it," Terry said.
The former defender noted that younger players will improve from their match minutes, though some squad members have shown they are not up to standard.
