Fiorentina had taken an early lead, but Lucas Castro made the most of two Cristiano Biraghi defensive errors for the Chievo victory.
The Viola were still smarting from a very controversial 1-1 draw with Atalanta last week, which saw the club protest against the refereeing and limited use of VAR. It was a homecoming for Cyril Thereau, who spent much of his Serie A career at the Bentegodi, as did Coach Stefano Pioli. Chievo missed Riccardo Meggiorini and Massimo Gobbi, but had ex-Fiorentina defender Nenad Tomovic and wanted to continue their three-round unbeaten streak.
Fiorentina had won eight of their last nine Serie A meetings with the Flying Donkeys, drawing the other, and kept a clean sheet in the last five.
The visitors, playing all in green, broke through when Lucas Castro was pressed into losing possession, Thereau whipped in a cross for Giovanni Simeone’s glancing header into the far top corner.
However, Chievo equalised thanks to some comical defending. Cristiano Biraghi hit a fresh-air clearance, allowing Lucas Castro to control and finish at the back post relatively undisturbed.
Simeone almost completed his brace, Stefano Sorrentino belying his years with an acrobatic fingertip save on another header from Jordan Veretout’s free kick.
Straight after the restart, Biraghi was caught ball-watching again, as Castro snuck up behind him for a looping header at the back post from Perparim Hetemaj’s cross.
Thereau volleyed a Milan Badelj cross into the path of Simeone, who just failed to get the final touch, but the Viola were surprisingly uninspired.