Inter Milan moved within touching distance of retaining their Serie A title after a fluke own goal from Udinese's Mauricio Isla sealed an undeserved 1-0 win on Sunday.
With eight games remaining, Inter have extended their lead to nine points after second-placed Juventus earlier allowed Chievo striker Sergio Pellissier to score a hat-trick in a 3-3 draw in Turin.
Hosts Udinese had dominated Inter until Patrick Vieira charged into the box in a rare foray forward on 77 minutes and the ball rebounded off Isla's leg into the net.
Udinese's Fabio Quagliarella had two penalty shouts turned down and a shot expertly tipped over by Inter goalkeeper Julio Cesar, who later went off injured.
Inter were extremely lucky but Juve, who host the champions on April 18, only had themselves to blame for letting Pellissier head in a stoppage-time equaliser.
"Today is a splendid day which I'll remember for a long time," the 29-year-old Italian told Sky television.
Chievo, who have steadily moved away from the relegation zone in the last month, went ahead midway through the first half when Pellissier took advantage of Giorgio Chiellini's mistake to round Gianluigi Buffon and score.
Defender Chiellini, wearing a mask to protect a broken nose, made up for his error by smashing the ball in off the bar but Pellissier grabbed his second just before the break when this time he outpaced Olof Mellberg.
Chievo defenders Santiago Morero and Mario Yepes both touched the ball for an unfortunate own goal early in the second period and Juve went ahead with 11 minutes left when Vincenzo Iaquinta headed in Mauro Camoranesi's cross.
Pellissier was not to be denied, however, and Chievo deserved their draw against a lethargic Juve, who substituted the ineffective Alessandro Del Piero at halftime.
Lacklustre AC Milan, in a distant third, beat relegation-threatened Lecce 2-0 thanks to two injury-time goals.
Philippe Senderos and Ronaldinho both claimed the first after getting their heads to a free kick and Filippo Inzaghi soon netted a second for the Rossoneri, who left out David Beckham.
Substitute Thiago Motta netted in the second half to keep Genoa two points clear in fourth spot with a 1-0 win at almost doomed bottom side Reggina.
Fiorentina, in fifth, needed Alberto Gilardino's late goal to win 2-1 at Atalanta while sixth-placed AS Roma are three further back after two contentious penalties from Francesco Totti sealed a 2-1 home win over fourth-from-bottom Bologna.
Torino, under new boss Giancarlo Camolese, remain two behind Bologna after losing 1-0 at Palermo.