Nikola Kalinic grabbed a hat-trick as Fiorentina came from behind to thump Cagliari 5-3.The hosts took the lead after just two minutes when Davide Di Gennaro headed Nicola Murru's cross home. But Croatia striker Kalinic hauled Fiorentina level when he nodded in Cristian Tello's 20th-minute corner.Two goals in five minutes from Federico Bernardeschi then turned the game on its head and Kalinic fired the fourth shortly before half-time.Kalinic completed his hat-trick eight minutes into the second half with another header from another Tello cross.Marco Capuano and Marco Borriello pulled goals back but Fiorentina held on.