Fiorentina announced on Saturday that they had fired coach Vincenzo Montella with the club struggling in 14th in Serie A.
"Vincenzo Montella has been relieved of his duties as head coach of the first team," the club announced on its web site. "The decision was taken following a long and detailed analysis of the team's performances and results."
"Given the need to rediscover the necessary grit and determination on the pitch and produce an immediate turnaround, the owners and management decided that a change of coach was the best option," the club continued.
Fiorentina promised a new coach would be announced "in the next few days".
Montella, a 45-year-old former Italy winger, managed Fiorentina from 2012-15 leading the club to two fourth-place finishes in Serie A before he was fired. After spells in charge at Sampdoria, AC Milan and Sevilla, he returned to Florence in April.
Fiorentina lost 4-1 at home to Roma on Friday and have taken just two points from their last seven games.
Buoyed at the start of the season by the arrival of Franck Ribery, the team has been struggling since the Frenchman suffered a serious ankle injury that will keep him out until February.
Fiorentina have started their winter break and do not play again in Serie A until January 6.