Napoli boosted their automatic Champions League qualification hopes by beating Roma in a game which leaves Juventus a step closer to the Serie A title. Dries Mertens' double for Napoli has taken them to within two points of second-placed Roma, while Juventus will move 10 points clear if they beat Udinese on Sunday (14:00 GMT). Belgium attacker Mertens dinked home Marek Hamsik's through ball to open the scoring and converted Lorenzo Insigne's pass to make it 2-0. Roma midfielder Daniele de Rossi was fortunate not to be sent off when he kicked keeper Pepe Reina. Napoli coach Maurizio Sarri was dismissed for his protests. Kevin Strootman scored late on for Roma, and Diego Perotti almost levelled in injury time with Reina producing a magnificent save to deny him.