ROME (Reuters) - Serie A leaders Napoli were on the right end of two borderline offside decisions, the first awarded with the help of the video replay system (VAR), as they beat AC Milan 2-1 on Saturday to send their rivals back into crisis mode.
In the earlier game, AS Roma beat arch-rivals Lazio by the same score to win the first derby since the retirement of their talismanic playmaker Francesco Totti.
Totti, who retired last season after 25 years with Roma which included a record 44 derby appearances, watched from the stands.
It was a nightmare match for Lazio defender Bastos who gave away the penalty for Roma's first goal and lost possession at the start of the move which led to Radja Nainggolan striking the winner.
Napoli's win left them with 35 points from 13 games, four ahead of titleholders Juventus who are away on Sunday to a Sampdoria side who boast a 100 percent home record.
Roma moved above Lazio to third with 30 points from 12 games, ahead of Inter Milan on goal difference and two points clear of their neighbours.
Lorenzo Insigne, overlooked by Italy for the second leg of their World Cup qualifying playoff against Sweden on Monday when a goalless draw meant they failed to qualify, opened the scoring with the help of VAR in the 33rd minute.
Insigne collected Jorginho's long pass forward, left the Milan defence standing and clipped the ball past Gianluigi Donnarumma only to see his goal chalked off for offside.
Milan were preparing to re-start with a free kick when referee Daniele Doveri signalled that the VAR was being consulted, and then awarded the goal.
Piotr Zielinski struck the second in the 73rd minute, beating Donnarumma with a first-time shot after being sent clear by an astute Dries Mertens pass as the Milan defence appealed for offside.
Despite the protests, the referee gave the goal without consulting VAR.
Alessio Romagnoli volleyed one back for Milan in stoppage time but it was too late to stop his big-spending side from slumping to a sixth defeat in 13 games.
Roma clocked up their sixth successive win in all competitions and ended Lazio's run of nine wins in a row with their victory at the Stadio Olimpico.
After a goalless first half, Roma quickly took control as Diego Perotti and Nainggolan scored in a four-minute spell.
Perotti converted a penalty after Bastos tripped Aleksandar Kolarov, then Nainggolan scored with a low diagonal shot from outside the box after the hapless Angolan lost possession.
"When you make those sort of mistakes, you don't win derbies," said Lazio coach Simone Inzaghi. "Those four minutes condemned us to defeat."
Roma needlessly conceded a penalty when Kostas Manolas, under no pressure in the area, tried to cushion a cross on his chest but the ball hit his upper arm.
After consulting the VAR, the referee pointed to the spot and Immobile smashed the ball home in the 72nd minute.
(Writing by Brian Homewood in Bern; Editing by Christian Radnedge)
