Defending champion Juventus again slipped up in the Serie A title race as it was held to 1-1 by struggling Genoa on Saturday.
Juventus has won just one of its four league matches in 2013. It is six points ahead of Lazio, which lost 1-0 to Chievo Verona, and Napoli, which travels to Parma on Sunday.
After a first half entirely devoid of a shot on target, Juventus broke the deadlock 10 minutes after halftime when Fabio Quagliarella tapped in Stephan Lichtsteiner's cross.
However, Genoa drew level in the 68th minute when former Juventus striker Marco Borriello dove low to head in Juraj Kucka's cross, nine minutes after coming off the bench.
Juventus had several chances to snatch all three points, including and substitute Sebastian Giovinco's free kick crashing off the left post eight minutes from time.
There was late drama as Juventus appealed furiously for a penalty after Andreas Granqvist kicked the ball onto his own hand in stoppage time. The referee waved play on but protests continued after the final whistle, with coach Antonio Conte fuming.
"I accept it if someone tells me 'I made a mistake,' I don't accept it when they tell me 'I didn't feel like it.' This is not football," Conte said. "If I hear certain things, 'shame on you' is the very least I can say. I want fairness. The penalty was blatant.
"There's nothing to explain or clarify. Everyone saw what happened. I can accept a mistake but not that the referee tells me 'I didn't feel like it.' The referee behind the goal gave the penalty, but he said he didn't have the heart."
It was a positive start for Davide Ballardini, who replaced Luigi Del Neri to become Genoa's third coach of the season.
"Talking about individual incidents is a great limitation of our football culture," Ballardini said. "In that case, we could talk about the Mirko Vucinic handling offence in the first half, but we'd never hear the end of it."
Earlier, Lazio fell to its first defeat in 17 matches in all competitions.
Lazio dominated much of the game and Chievo failed to have a shot on target in the first half.
However, Chievo scored shortly after the hour mark when Bojan Jokic's effort hit the crossbar and Alberto Paloschi tapped in the rebound.
Paloschi was involved in a bizarre incident early in the first half after his volley from near the centre-circle flew over the bar. Watching the long-range shot, Lazio goalkeeper Federico Marchetti ended up bringing the goal's netting down and the match was halted for several minutes.