Xavi has backed Marcos Alonso to play a big part in Barcelona's quest for more trophies after he signed a new contract on Friday.
Alonso arrived at Camp Nou in September as a free agent after leaving Chelsea, putting pen to paper on a deal until the end of this season.
The left-back has extended his stay with the LaLiga leaders by a further 12 months, with his buyout clause remaining at $54million.
Alonso has made 19 appearances in his first season with the Blaugrana, scoring twice and celebrating a Supercopa de Espana triumph this month following a win over fierce rivals Real Madrid.
Barca head coach Xavi welcomed the 32-year-old's decision to sign a new deal.
He said: "I am really happy with Marcos. Firstly, as a person and as a professional inside the dressing room, where he has adapted really well.
"But also as a player. He is solid, mature and experienced. He has been a top-level signing and will be really important for us moving forward."
Teenager Angel Alarcon has also signed a new contract with the Catalan giants, keeping him at the club until 2025 with a mammoth $435m release clause.