Juventus missed the chance to take a big step toward a ninth successive Serie A title in a 4-2 loss at AC Milan, while Lazio defender Patric was sent off for biting Lecce's Giulio Donati.
Juventus could have extended their lead at the top of the table to 10 points with a win and a tight first half finished goalless after Zlatan Ibrahimovic had a goal ruled out for offside shortly before the break.
But Adrien Rabiot broke the deadlock two minutes after the restart by curling a strike into the top-right corner with Cristiano Ronaldo doubling Juventus' lead six minutes later.
However, Milan turned the match around completely in the space of five minutes.
Ibrahimovic converted a penalty in the 62nd minute following a handball from Leonardo Bonucci before two quickfire goals from Franck Kessi and substitute Rafael Leo.
Milan extended their advantage 10 minutes from full time when Giacomo Bonaventura capitalised on an error from Juventus defender Alex Sandro to set up Ante Rebic.
Elsewhere in Serie A, Lecce missed a penalty and also had a goal disallowed, but still managed an upset win over title-chasing Lazio.
Fabio Lucioni and Khouma Babacar scored for Lecce after Felipe Caicedo had given Lazio an early lead.
Lazio's bad night was made worse when defender Patric was sent off for biting Giulio Donati in an incident that could lead to a lengthy ban.
Lazio were just a point behind Juventus when the season was halted because of the coronavirus pandemic. They had been on a record unbeaten run of 21 games but the Roman side have lost three of their five matches since the season resumed.
La Liga: Atleti held by Celta
Atletico Madrid were held to a 1-1 draw with relegation-threatened Celta Vigo, missing the chance to get closer to a Champions League spot.
Alvaro Morata put Atletico ahead in the first minute at the Balaidos Stadium, converting a cross from Angel Correa, but Fran Beltran equalized for the hosts with a neat volley in the 49th minute, hitting the top corner with a shot that lobbed over Atletico goalkeeper Jan Oblak.
Diego Simeone's team are three points ahead of fourth-place Sevilla and nine ahead of fifth-place Villarreal, extending their unbeaten run to 15 games.
It was the second straight draw for Celta, who opened a seven-point gap to the relegation zone but could lose some ground depending on other results.
Elsewhere, 19-year-old South Korea midfielder Lee Kang-in scored in the 89th minute to help Valencia end a four-game winless streak with a 2-1 victory over Real Valladolid.
Lee scored with a low left-foot shot from outside the area to keep Valencia in the fight for a Europa League spot. They are one point behind seventh-place Real Sociedad with three games to go. Valladolid, who have two wins since the break, stay in 13th place.