Juventus failed to win for a fifth successive Serie A game when Jose Castillo scored deep in stoppage time to give relegation-threatened Lecce a 2-2 draw on Sunday.
Pavel Nedved, due to retire at the end of the season, had scored twice to help third-placed Juve come from behind but they trail leaders Inter Milan by 11 points with four to play.
Second-placed AC Milan, who host Juve next Sunday, are seven behind Inter after in-form Filippo Inzaghi and Kaka netted either side of the break in a comfortable 2-0 win at Catania.
Inter, 2-0 winners over Lazio on Saturday, will seal their fourth successive scudetto if they win at Chievo next Sunday and Juve beat Milan.
The chances of a Juve victory at the San Siro look remote, however, after Claudio Ranieri's side put in another nervous performance against Lecce.
"We will try to put the situation right as quickly as possible to not ruin a good season," Ranieri told reporters.
"If a coach maintains the faith of the club at the end of the season he stays, otherwise he goes."
The game in Turin had been due to be played behind closed doors because of racist chanting against Inter last month but Juve won a temporary injunction to lift the ban.
However, Juve fans used the occasion to protest against Ranieri and club executives, especially after Axel Konan put Lecce ahead on 11 minutes despite looking offside.
The disappointing Alessandro Del Piero was hauled off at halftime and Juve improved after the break, Nedved firing in twice with his left foot but earning a booking which rules him out of the Milan game.
The mood in the stadium changed little despite Juve taking the lead, with fans also protesting against plans to bring Fabio Cannavaro back to the club from Real Madrid.
Argentine striker Castillo then headed in from close range to put second-bottom Lecce two points behind fourth-bottom Torino, who lost 1-0 at Fiorentina.
Juan Vargas's scrappy goal kept the Florence club in the fourth Champions League spot and put them just five behind Juve, who occupy the last berth for automatic qualification into next season's group stage.
Fifth-placed Genoa stayed a point behind after Argentina striker Diego Milito bagged a hat-trick in a 3-1 win over Sampdoria in a very lively city derby.
Genoa had Matteo Ferrari and Thiago Motta sent off as tempers flared while Samp goalscorer Hugo Campagnaro also saw red.
Inconsistent AS Roma are far from secure in a Europa League spot after a 0-0 draw with Chievo at the Stadio Olimpico where home supporters chanted against the players and club owners.