Serie A leader Napoli's title hope suffered a setback when they collapsed to a 4-2 defeat at home to AS Roma Saturday, while Paulo Dybala scored from a seemingly hopeless position in stoppage time to give rival Juventus a 1-0 win at Lazio.
Dybala's goal gave Juve their 10th successive league win, while Napoli saw their own 10-match winning run in Serie A ended by two goals from Edin Dzeko and one apiece from Cengiz Under and Diego Perotti.
Napoli, beaten for only the second time this season in the league, lead with 69 points from 27 games but Juve are only one behind and, crucially, have a game in hand at home to Atalanta on March 14, the fixture having been snowed off last Sunday.
Roma were helped by another outstanding performance from Brazil goalkeeper Alisson who made a series of saves at important moments with Lorenzo Insigne his chief victim.
Napoli, playing after the Juve game had finished, got off to a flying start when Insigne put them ahead after six minutes but Under levelled one minute later with a deflected shot which flew over Pepe Reina.
Dzeko put Roma ahead with a looping header from Alessandro Florenzi's cross in the 26th minute and the Bosnia forward added the third in the 73rd minute when he cut inside his marker and curled a shot beyond Reina's reach.
In doing so, he became the first player to score at least 50 goals in three of the top-five leagues in Europe - 66 in the Bundesliga, 50 in the Premier League and 50 in Serie A.
It became a rout when Perotti fired home six minutes later, taking full advantage of a poor clearance by Mario Rui, although Dries Mertens made the score more respectable in stoppage time, finding the net with a low drive from outside the area.
Lazio had the better of their game against Juve until the titleholder, in typical style, snatched all three points at the death with their third shot on target.
Surrounded by three defenders, Dybala collected the ball outside the Lazio area with his back to goal, turned and flicked the ball through an opponent's legs, fell under a challenge from another and still managed to fire past Thomas Strakosha from on the ground.
Juve kept a clean sheet for the seventh consecutive time in the league and the only team to have scored against them in any competition this year are Tottenham Hotspur, who host the Turin side Wednesday in the second leg of their Champions League last-16 tie.
The defeat completed a tough week for Lazio who lost their Coppa Italia semi-final on penalties to AC Milan Wednesday.
(Grassi 48) Bologna 0
Lazio 0 Juventus 1
(Insigne 6, Mertens 90+2) Roma 4
(Under 7, Dzeko 26, 73, Perotti 79)
Genoa v Cagliari, Atalanta v Sampdoria, Benevento v Verona, Chievo v Sassuolo, Torino v Crotone, Udinese v Fiorentina and Milan v Inter
P W D L GD Pts
27 22 3 2 43 69
26 22 2 2 48 68
27 16 5 6 21 53
27 16 4 7 30 52