The Italy international had been strongly linked with a move to Genoa but the deal failed to materialise.
The 29-year-old, who joined the Viola from Milan in 2008, is nevertheless happy to remain in Florence.
"It has been a complicated summer for me," he said.
"Fortunately, though, I can now just concentrate on Fiorentina.
"I want to thank the fans who have shown me their faith and affection in these past few weeks - I'm happy and honoured to still be wearing the Viola shirt.
"Despite all of the rumours and negotiations about me, I'm happy to stay in Florence.
"I want to have a great season and I just can't wait to play."
Fiorentina will be looking to avoid a repeat of last year's dismal start to the campaign.
They won just one of their opening seven Serie A fixtures last term - a 2-1 win over Bari.
Sinisa Mihajlovic's side finished a disappointing ninth and will be hoping for better fortune this time around.
Rivals Bologna underwent a complete overhaul this summer.
The Rossoblu, who narrowly avoided relegation last season, have made numerous signings in a bid to improve from last term's 16th-placed finish.
New coach Pier Paolo Bisoli will be hoping the arrival of midfielder Alessandro Diamanti from Brescia and strikers Federico Rodriguez and Robert Acquafresca will prove successful.
The visitors will be without suspended trio Jose Angel Crespo, Daniele Vantaggiato and Gaston Ramirez.
Veteran forward Marco Di Vaio will lead Bologna's attack on Sunday.