Pochettino's recruitment appears to have been in the pipeline for some time after he revealed he had been studying the Southampton squad "for several weeks".
That will do little to appease the Saints supporters who are angry that Nigel Adkins was sacked despite leading the club to 15th in the Barclays Premier League after back-to-back promotions.
Pochettino confirmed the signing of Norwegian centre-back Vegard Forren from Molde on a three-and-a-half year contract, describing him as "a footballer with great promise".
But that positive news was overshadowed by the reaction to Pochettino's appointment, with former Southampton captain Matt Le Tissier saying it had turned the club into a "laughing stock".
Pochettino's first game in charge will be on Monday against Everton and he said via an interpreter: "I really want to convince the fans and hopefully they will take me in as they did the previous manager.
"It is a great challenge to be here as part of this project and (winning) the kindness of the supporters is one of the biggest challenges that I have.
"I am sure they will be supporting the club for the 90 minutes the game will last. Fans are free to express their feelings. I can't tell them what to feel but I have a lot of respect for how they react.
"I hope I can convince them with hard work, honesty and that they enjoy the way the club plays and they feel honoured and proud how the team is playing."
