Andrea Pirlo conceded Juventas missed Cristiano Ronaldo's "killer instinct" as the Italian champions fell to their first league defeat in two decades to Atalanta on Sunday leaving their participation in next season's Champions League at risk.
Leaders Inter Milan edged towards the Serie A title despite a 1-1 draw at Napoli, to pull 13 points ahead of Juventus who dropped to fourth place. Christian Eriksen snatched a point for Inter whose 11-match winning streak ended but who hold a nine-point advantage on AC Milan as they target a first league title since 2010.
Milan earlier got back winning in the San Siro after two months 2-1 against Genoa. Juve's nine-year reign as champions looks set to end with nine games left, and their European hopes are also at risk.
Substitute Ruslan Malinovskyi struck three minutes from time in Bergamo with a shot that took a deflection off Alex Sandro as Atalanta won 1-0 to move third.
Juventus were playing without injured Ronaldo, the top scorer in Serie A with 25 goals this campaign. "We knew it would be tough against Atalanta," said Juve coach Andrea Pirlo. "Ronaldo is our finisher, he adapts to these matches, because he's a champion. He's a penalty area killer. Today we had our chances, we didn't use them and we were punished by an episode."
Juve have failed to win any of the four matches they have played this season without 36-year-old Ronaldo.
But they held fourth spot two points ahead of Napoli whose six-match winning streak at home was stopped by Inter.
In Naples, top Inter scorer Romelu Lukaku rattled the woodwork either side of Napoli's opener, an own-goal following a blunder from visiting goalkeeper Samir Handanovic.
Lorenzo Insigne tried to connect with Victor Osimhen to finish off with Handanovic intercepting the ball only to lose control after colliding with Stefan de Vrij sending into his own net.
Eriksen pulled Inter level 10 minutes after the break rifling in from just outside the penalty area.
"I'm very happy and proud of this group of guys who have grown significantly in many ways," said Inter coach Antonio Conte. "On other occasions we would have lost the game, we would have fallen on that goal conceded. Instead the team reacted, they know what they are capable of and want to fight for something important."
Milan back winning in San Siro
In Milan, Gianluca Scamacca's 68th-minute own goal kept the seven-time European champions on course for a return to Champions League football next season.
Stefano Pioli's side had not won their last six games in the San Siro in all competitions and were playing without suspended forward Zlatan Ibrahimovic.
"We wasted a lot, we could have finished it earlier, but the important thing is the spirit to stay in the game until the very end," said Pioli, who has given up on catching Inter. "Inter have taken too many points to think that we can still fight for the Scudetto (league title). Winning was important. We will have to face important teams, Atalanta, Juventus, Lazio, from here to the end they will all be difficult."
Ante Rebic put Milan ahead in the 13th minute with Rafael Leao, taking the place of Ibrahimovic, missing a chance for a second minutes later. A Mattia Destro header against his former club pulled 14th-placed Genoa level eight minutes before the break.
Mario Mandzukic came off the bench for his first appearance in over two months just after the hour and had a role in the winning goal, which Scamacca guided past his own goalkeeper from a Hakan Calhanoglu corner. In Rome, Lazio beat Benevento 5-4 in a match between coaching brothers Simone and Filippo Inzaghi to stay in the chase for the Champions League.
Ciro Immobile scored twice for the hosts and also missed a penalty as sixth-placed Lazio are four points behind Juventus having played a game less. Roma's Champions League ambitions took a knock with a 3-1 defeat at Torino, who boosted their chances of top-flight survival.
Roma have taken four points from the last five games, and are stuck in seventh position, eight points off the Champions League berths.