The Serie A side edged into a 2-1 aggregate lead thanks to Mario Gomez’s 54th-minute strike after a stalemate in the first leg at White Hart Lane.
Mohamed Salah, who joined Fiorentina on loan from Chelsea in the January transfer window, sealed la Viola’s place in the last-16 draw with 19 minutes remaining in Florence.
Fiorentina defender Richards, who completed a season-long loan move from Manchester City last summer, uploaded a photo of his Italian side’s players celebrating their triumph.
Richards wrote: “That’s how much it meant to us to beat Spurs over 2 legs! @netoo_89”
Salah has made an immediate impact at Fiorentina following his temporary switch to the club after Juan Cuadrado joined Chelsea in a £23.3m deal.
The Egypt international has scored three goals and made one assist in five appearances, and Salah posted a photo to Instagram following the win.
Salah said: “What a fantastic game boys”
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