The midfielder says he was lucky to have been a part of the current Bayern Munich boss' "extraordinary project" at Camp Nou.
Guardiola enjoyed a trophy-laden four years at Camp Nou, during which his side secured three La Liga titles and two Champions League triumphs.
The 42-year-old departed the Spanish champions in 2012, taking a short sabbatical before joining Bundesliga holder Bayern Munich in the offseason. And Xavi hailed the "extraordinary project" engineered by Guardiola during his time in Spain.
"Pep made his job in Barcelona. We are so proud he was our manager," he said. "(We had) four years when we won plenty of trophies. He led an extraordinary project until he decided to leave for a gap year and nowadays he is doing a brilliant job in Bayern Munich.
"Obviously, we miss things from him, as (we do) the other managers who left the club. We have another coach, we had [Tito] Vilanova last year and Tata [Gerardo] Martino this season. Each person has a different way to work. Guardiola had his way, Vilanova too and Martino as well. All of them are good managers and we were lucky with Guardiola because we made history."