The now 35-year-old joined Celta Vigo back in August 2024 as a free agent following a two-season stint at Barcelona.
Alonso has been a key player for them ever since, making 76 appearances across all competitions, and helping them to a sixth place LaLiga finish last season.
He has now revealed that he had ‘significant offers’ to leave the club this summer but has decided to turn them down.
"The truth is, I took the first two weeks to rest. The following week it was practically a done deal, and all that was left was the signature," said Alonso.
"But to avoid rushing my return, I signed the day I came back from vacation.
"It's true I had some significant offers, but my priority is to give continuity to the project, to be close to home, and the group we have here is important.
"There were quite a few messages from team-mates and the coaching staff asking me to stay, and that influenced my decision.
"I have to thank the club for their confidence. We're carrying out a very exciting project, and I wanted to stay here, give it continuity, and continue growing as a team and as a club.
"Two years wasn't a priority; I decide year by year, and if things are going well, I'll stay for two years, and if not, it won't be too difficult for them to let me go."