Fiorentina looked to be suffering a hangover from their mid-week UEFA Cup defeat to Ajax as they labored to a narrow win over 10-man Chievo.
Relegation-battlers Chievo went ahead through Santiago Morero and lead for almost an hour before Alberto Gilardino leveled the score with less than 20 minutes remaining.
A frantic final 10 minutes then saw Vincenzo Italiano dismissed for his second yellow card before Adrian Mutu, with the last touch of the game, ensured all three points remained in Florence.
The hosts had the first real chance of the game in the eighth minute. Luciano Zauri crossed a nice ball from the right which Alberto Gilardino glanced wide with a header from inside the area.
Two minutes later Gilardino again came close with a header, this time from a Stevan Jovetic corner from the left.
However, it was the Ceo who took a surprise lead in the 13th minute. Michele Marcolini whipped in a corner from the right which Mario Yepes headed over the pack into the path of Morero, who tapped home unmarked.
In the 18th minute Marcolini played a short one-two pass with Bentivoglio from the corner spot before seeing his shot from the corner of the area deflected just wide of the post.
Fiorentina had a good chance to level in the 22nd minute as Mutu acrobatically volleyed a Zauri cross just over the bar following some good build up play from the Gigliati.
For the rest of the half the Viola pressed forward but were unable to test Chievo goalkeeper Stefano Sorrentino, either through their own imprecision or they were repeatedly blocked by a sturdy Ceo defence.
The impressive Felipe Melo came the closest with a powerful shot from the edge of the area that took a deflection off a defender to whistle just over the bar two minutes before the break.
Ceo striker Sergio Pellissier forced a diving save from Fiorentina goalkeeper Sebastian Frey with the last action of the half before the Viola left the field to whistles from the home supporters.
At the break Fiorentina coach Cesare Prandelli took off Juan Vargas and Jovetic with Manuel Pasqual and Franco Semioli their replacements.
Four minutes into the second half Zdravko Kuzmanovic wasted a Viola counter attack by blasting wide much to the annoyance of his team-mates.
Riccardo Montolivo fared little better in the 55th minute as he fired a powerful shot just past the left post.
Chievo had a chance to double the score soon after at the other end as Stephen Makinwa beat Per Kroldrup on the right wing before aiming a diagonal shot just over the bar.
Instead, the hosts levelled in the 73rd minute after Pasqual floated across a lovely cross from the left wing which Gilardino headed into the far corner with Sorrentino well beaten.
Chievo's efforts to repel the Fiorentina onslaught were hampered in the 82nd minute as Italiano was shown his second yellow card for downing Kroldrup in full flight.
The hosts rallied for one final push which paid off with the last touch of the game.
Substitute Emiliano Bonazzoli pulled the ball back for Mutu in the right channel 22 yards out, and the Romanian scored his 12th goal of the season with an unstoppable effort which sparked ugly scenes as the visitors felt play should have been halted sooner as a player was on the ground at the halfway line.
