Cristiano Ronaldo scored his 19th goal this campaign but champions Juventus settled for a 1-1 draw at Hellas Verona in Serie A on Saturday.
The draw gives leaders Inter the chance to pull 10 points clear of Juventus when they play mid-table Genoa at the San Siro on Sunday.
Juventus are third and three points adrift of second-placed Milan who travel to Roma, two points behind the champions in fourth, on Sunday.
Ronaldo broke through four minutes after the break connecting with a perfect cross from Federico Chiesa.
But Andrea Pirlo’s side paid for their many absences including defensive duo Leonardo Bonucci and Giorgio Chiellini.
Antonin Barak headed in an equaliser with quarter of an hour to go to grab a point for his ninth-placed team.
Lazio’s European ambitions took a knock with a 2-0 loss at Bologna, days after a heavy defeat by Bayern Munich in the Champions League.
Ciro Immobile missed a penalty with goals in either half from Ibrahima Mbaye and Nicola Sansone sealing all three points for Bologna who snapped their 15-match winless league run against the Romans.
“The missed penalty set the tone for the game,” said Lazio coach Simone Inzaghi.
Inzaghi’s side showed signs of fatigue as they came off a 4-1 Champions League last 16, first leg loss to holders Bayern Munich.
“We must forget about these two defeats which hurt. An ambitious team like ours needs to roll up our sleeves and do better.”
Lazio have lost momentum since losing to Inter Milan in the league two weeks ago, and next host Torino before travelling to Juventus.
Last season’s European golden shoe winner Immobile had a chance to score from the spot after Joaquin Correa was tripped in the box with goalkeeper Lukasz Skorupski easily holding the striker’s weak effort.
And 11th-placed Bologna got the breakthrough two minutes later when Mbaye tapped in a rebound after Pepe Reina parried a Riccardo Orsolini volley.
Musa Barrow set up Sansone for the second after 64 minutes as Lazio’s 19-game league scoring streak ended, two short of their record run in 1956.
Lazio stay sixth on 43 points and could also be overtaken by Napoli on Sunday, while European rivals Atalanta travel to Sampdoria.