Federico Chiesa hit the woodwork for Fiorentina, but Daniel Ciofani snatched a late winner for Frosinone’s historic second consecutive victory.
Chiesa was back in the starting XI after recovering from a muscular problem, with Luis Muriel moved to centre-forward and Giovanni Simeone rested. Edimilson Fernandes and Marko Pjaca were still out of action. The Canarini missed Federico Viviani and Lorenzo Ariaudo, so Paolo Sammarco stepped in to midfield.
It was a dramatic start, as in the opening 90 seconds a Frosinone corner found the head of Bartosz Salamon, Alban Lafont acrobatically fingertipping it out from under the crossbar.
Moments later, the Viola went on the counter and Kevin Mirallas saw his strike parried by Marco Sportiello’s legs.
It remained wide open, Nikola Milenkovic nodding over from a set play, then Chiesa’s diving header wide at the back post from a Cristiano Biraghi cross.
Marco Benassi only glanced his head to a free kick, putting it over the bar, though Frosinone remained dangerous on the counter. Just before half-time, Milenkovic was back to clear a deflected Luca Paganini shot, then Lafont spilled the Andrea Beghetto follow-up, but scrambled it back under control.
Beghetto was booked for leaving stud marks on Vincent Laurini’s ribs, but it was not a red because he tried to pull out as they both came sliding in on the wet turf.
Benassi again came close after the restart, Pezzella knocking back a free kick for him to head wide unmarked from 12 yards.
Frosinone risked an own goal with a pull-back ricocheting past the near post off one of their defenders, leaving Sportiello stranded.
Jordan Veretout drilled off target from distance, but the Canarini wasted a golden opportunity on 69 minutes when Edoardo Goldaniga turned his free header wide from a corner.
Fiorentina’s defending was poor and Luca Paganini ghosted in at the back post, steering his header across the face of goal and just wide of the far post.
Chiesa came so close to giving the Viola victory at the 81st minute, cutting inside from the left and his right-foot curler smacking against the far upright with Consigli well beaten.
It proved costly, because moments later Frosinone took the lead. Andrea Pinamonti rolled across for substitute Daniel Ciofani, who took a touch on the edge of the box and rifled in the right-foot angled drive into the far bottom corner.
Ciofani converted a penalty at the 103rd minute to beat Parma 3-2 last week and was again keeping Frosinone’s slender hopes of Serie A safety alive with a second consecutive victory. The club had never previously won two on the bounce in the top flight.
The result means Fiorentina avoid a club record sixth consecutive Serie A home stalemate, but that is scant consolation for a season that has fizzled out in dismal fashion.
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