Barcelona have confirmed that Cristian Tello will leave the club for Real Betis for an initial fee of €4 million.
Tello has spent the last 18 months at Fiorentina but was due to return to Barca for pre-season, where he had one year remaining on his current contract.
However, new Betis coach Quique Setien pushed hard for the winger, who returns to La Liga for the first time since 2014.
"FC Barcelona and Real Betis Balompie have reached an agreement for the transfer of Cristian Tello to the Andalucian side for four million euros with a potential one million more to come," the Catalan club said in a statement.
"FC Barcelona reserves the right to participate in the future sale of the player."
Tello, 25, came brought Barca's La Masia academy -- although he spent two years away at Espanyol before retuning in 2010 -- and made his first team debut under Pep Guardiola in 2011.
He went on to make 59 appearances for the club before joining Porto on loan three years ago.
Porto cut his two-year loan deal short after 18 months, though, allowing him to move to Italian side Fiorentina, where he has spent the last year-and-a-half.
But the Serie A club opted against making his deal permanent this summer.
Tello becomes Betis' third signing in what looks set to be a busy summer in Seville, with deals for Sergio Leon and Victor Camarasa already completed.