Champions Juventus's march towards a seventh consecutive Serie A title was stalled on Saturday by a goalless draw at struggling SPAL that kept the suspense alive in Italy.
Massimiliano Allegri's side had been bidding to open a seven-point cushion on Napoli, who can now close the gap to two points on Sunday when they host Genoa, who are 13th.
Juventus's 12-match league winning streak came to a halt as the champions lacked inspiration against the promoted side from Ferrara with normally reliable goal machines Paulo Dybala and Gonzalo Higuain failing to feature.
Faced with a solid and well-organised SPAL unit, Juventus's only chances came through Alex Sandro after 11 and 87 minutes and a late Mario Mandzukic header.
And there was also a worry three weeks before their Champions League quarter-final first leg against Real Madrid with Giorgio Chiellini leaving the pitch 10 minutes before the end with a thigh injury.
"It's an important point that allows us to continue our fight for Serie A safety," said SPAL striker Mirco Antenucci.
"This is result is something to be proud of and we?re really happy with it."
Earlier Sassuolo got their first win since December, triumphing 2-1 to condemn Udinese to a fifth consecutive defeat.
Iraqi international Ali Adnan conceded an own goal after 42 minutes but two minutes later Seko Fofana pulled hosts Udinese level.
Stefano Sensi scored the winner 15 minutes from time to give Sassuolo breathing space as they move away from the relegation zone.
© 2018 AFP