Fiorentina have indicated to Real Betis that they will pay the full €11m to trigger their option to buy on loan defender German Pezzella.
The 26-year-old has starred in Serie A this season for La Viola, starting 25 league matches, with ABC de Sevilla now stating the option will be triggered in May, when it expires.
The Argentine international joined Los Verdiblancos from River Plate in 2015 for €2.5m but failed to impress Coach Quique Setien, who sanctioned his exit last year.
Reports had suggested Atletico Madrid, Inter and Zenit Saint Petersburg all held a lingering interest in the central defender, with La Viola keen to tie down his services.
Such funds will allow Betis – who signed Marc Bartra from Borussia Dortmund in January – to continue to reinvest in their squad this summer.