AC Milan goalkeeper Gianluigi Donnarumma frustrates Napoli. (AFP/MIGUEL MEDINA) |
The title could be tied up by next Sunday when Juventus and Napoli go head-to-head in a top of the table clash in Turin.
Juventus would have to win on Wednesday at Crotone and Napoli lose at home against Udinese, while the champions would also have to win next Sunday's game for the title to be decided.
"Napoli are having a sensational campaign, they are still right up there and I think the next two games could be almost decisive for the Scudetto," said Juventus coach Massimiliano Allegri.
"We are absolutely not favourites for the Scudetto. I want to thank everyone today, because it's not easy to win like this after such a draining experience as the Champions League."
Juventus showed they had put their midweek Champions League defeat to Real Madrid behind them as they were greeted with a banner "Proud of You" and applause for captain Gianluigi Buffon who was sent off in Madrid.
Brazilian Douglas Costa was the architect of the victory coming off the bench in place of the injured Miralem Pjanic to set up all three goals.
Costa crossed for Mario Mandzukic who volleyed under the bar just before the break, and dinked another for Benedikt Howedes whose diving header found the mark on the hour mark.
The Brazilian then set-up Sami Khedira for the third with 15 minutes to go, with Buffon denying Duvan Zapata a late consolation goal for Sampdoria.
"Douglas Costa was meant to come on, not quite that early, but it was part of the plan," said Allegri.
"We played with focus, calm and intelligence. Then Pjanic did the rest! He just had a thigh twinge and it was best to come off."
Juventus now have have 84 points from 32 games, six ahead of second-placed Napoli with six games to go.
A Gianluigi Donnarumma wonder save in added-on time denied Napoli a last-gasp victory in the San Siro.
The 19-year-old Italian - who became the youngest player to reach 100 Serie A appearances on Sunday - dived to keep out substitute Arkadiusz Milik's goal-bound effort two minutes into added-on time as Napoli lost further ground on Juventus.
Napoli - bidding for an elusive third title after those won in 1987 and 1990 - now have 78 points from 32 games.
"We don't care what Juventus do," said Napoli coach Maurizio Sarri after a third draw in their past five games.
"We are on our journey, the team did well and if we had played this performance with this result in the first half of the season, we would have been praised for it.
"Aside from a couple of crosses, we allowed Milan absolutely nothing."
AC Milan remain sixth and within the Europa League places but look too far behind for the Champions League.
"As long as we're still mathematically in contention, we believe. But there's a lot of points between us and fourth place," said Milan coach Gennaro Gattuso.
Roma and Lazio are in third and fourth place respectively on 61 points after playing out a goalless Roman derby in the Stadio Olimpico.
Inter Milan missed the chance to pull ahead of both teams and back into the Champions League places with a goalless draw at Atalanta, leaving Luciano Spalletti's side a point behind in fifth.
The bitter Roman rivals both showed signs of fatigue after their varying European fortunes midweek.
Roma - who shocked Barcelona to advance to the Champions League semi-finals - had more chances with Bruno Peres hitting the post before the break and an Edin Dzeko header hit the crossbar in added-time.
Lazio - dumped out of the Europa League - held on despite being down to ten men after Stefan Radu was sent off for the final ten minutes.
Meanwhile, rock-bottom Benevento earned their first away point with a 2-2 draw at Sassuolo, thanks to a double from Malian striker Cheick Diabate who has scored seven goals in six matches.
Italian Serie A results:
Fiorentina 0 SPAL 0
Bologna 2 Verona 0
AC Milan 0 Napoli 0
Sassuolo 2 Benevento 2
Juventus 3 Sampdoria 0
Lazio 0 Roma 0
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