Brazilian midfielder Felipe Melo scored the only goal of the contest at the Giuseppe Meazza stadium in the 56th minute, rising highest to meet Alex Telles’ corner.
To call Serie A newcomers Frosinone “minnows” is an understatement.
Fiorentina went second with 12 points when second-half goals from Jakub Blaszczykowski and Nikola Kalinic gave them a 2-0 win over promoted Bologna.
Felipe Melo’s powerful header gave Inter a 1-0 win over Verona and left Roberto Mancini’s Inter as the only team with 15 points from five games, all of them by one-goal margins.
The Juventus coach is not anxious about his side’s chances of success this season, despite the Bianconeri facing Napoli in Serie A and Sevilla in the Champions League in their next two fixtures.
Simone Zaza scored his first goal for his new club to break the deadlock, yet Juventus paid the price for failing to capitalise on their dominance when Leonardo Blanchard nodded home an injury-time equaliser for the visitors.
“It was a mistake to allow Frosinone a corner in the last minute of the game”.
“We are paying for this situation with many points in the table now”.
Sampdoria had taken the lead through Eder, only for Roma to get back on level terms thanks to on-loan Chelsea winger Mohamed Salah.
Lazio 2-0 Genoa: Filip Dordevic and Felipe Anderson were on target for the home side as they cruised to victory.
Sassuolo lie third – 10 places ahead of Juve – after a 1-0 win at Palermo.