Napoli kept their title hopes alive with a 4-2 win over Udinese on Wednesday as champions Juventus' path to a seventh consecutive Serie A title was stalled 1-1 at Crotone.
Nigerian forward Simy grabbed the equaliser for Crotone after 65 minutes with a spectacular overhead bicycle kick with shades of that scored by Cristiano Ronaldo in Turin last month.
"We didn't do so well tonight, even though the guys did everything possible," said Juventus coach Massimiliano Allegri.
"We were a plus six (points) and tonight was decisive for the Scudetto.
"The thing to do is stay calm, and play this championship until the end."
Napoli came from behind twice to cut the gap on Juventus to four points with five games remaining including next Sunday's top of the table clash between the two teams in Turin.
Maurizio Sarri's side were given an early scare at home with Czech Jakub Jankto putting Udinese ahead after 41 minutes.
But Lorenzo Insigne pulled Napoli back just before the break only for Swedish midfielder Svante Ingelsson to put Udinese in front again ten minutes into the second half.
But Raul Albiol, Arkadiusz Milik and Lorenzo Tonelli all scored in a ten-minute spree in the second half to condemn Udinese to their 20th defeat of the season.
Napoli had fallen six points adrift of leaders Juventus after last weekend's goalless draw at AC Milan with the champions closing in on the title.
Gianluigi Buffon was rested ahead of Sunday's game with Wojciech Szczesny in goal and Juventus looked to be on track after Alex Sandro headed in a Douglas Costa cross after 16 minutes in Calabria, before Simy struck on 65 minutes for the relegation threatened southerners.
Behind the leading duo the race for Champions League football next season continues with AS Roma - already through to the semi-finals of this year's competition - remaining third after a 2-1 win in Genoa.
Lazio are fourth with the same number of points as city rivals Roma, coming from two goals down to beat Fiorentina 4-3, ending the Tuscan side's eight-match unbeaten run.
In a crazy first half both sides were reduced to ten men while Jordan Veretout scored all three goals for Fiorentina.
Luis Alberto scored a brace for Lazio with Martin Caceres and Felipe Anderson completing the scoreline for the Romans.
Inter Milan remain fifth one-point outside the Champions League places after easily seeing off Cagliari 4-0 on Tuesday.
In the fight for Europa League spots AC Milan are sixth after a 1-1 draw against Torino with Atalanta seventh after a 3-0 win over rock bottom Benevento who could be relegated at the weekend.