Ronaldo missed two late chances as he came face to face with goalkeeper Andrea Consigli.
“It was a well played game,” Ronaldo said. “Sassoulo are strong and the game was intense and of course I am happy about my first goals.
“It is football (he said about his two mistakes). What matters is to win. Of course I was a little anxious after the move from Real, but now I am happy. I know I am working well and I am happy to be with my team-mates who are helping me as I am adapting to the Italian league.”
Juve did not threaten in the first half at Turin's Allianz Arena, while Ferrari had a header saved by Wojciech Szczesny, who also denied Alfred Duncan on 75 minutes. The keeper was beaten when substitute Khouma Babacar headed home in stoppage time.
Juve winger Douglas Costa came on in the second half and was red-carded after video review for spitting at an opponent in stoppage time.
Elsewhere, Genoa beat 1-0 Bologna, who had Erick Pulgar sent off in injury time, and Udinese and Torino drew 1-1.
Earlier in Rome, Roma squandered a two-goal lead in a 2-2 draw with visiting Chievo to slip seven points behind Juventus.
In stifling noon heat at Rome's Stadio Olimpico, Stephan El Shaarawy turned in a cross from Alessandro Florenzi, and Bryan Cristante profited from an Edin Dzeko assist to put Roma ahead. But Valter Birsa's great swerving shot and a Mariusz Stepinski clinical drive levelled matters in a hard-fought second half.
The Giallorossi inched onto five points, two behind Sassuolo, who are third on seven. Chievo have minus one point after being docked three last week in a trial for irregular bookkeeping.
Napoli have nine points after edging Fiorentina 1-0 Saturday, while Inter Milan (4) lost 1-0 at home to Parma and Sampdoria crushed Frosinone 5-0.
Empoli v Lazio and Cagliari v AC Milan play later Sunday. Spal v Atalanta completes matchday 4 Monday.
“It was a well played game,” Ronaldo said. “Sassoulo are strong and the game was intense and of course I am happy about my first goals.
“It is football (he said about his two mistakes). What matters is to win. Of course I was a little anxious after the move from Real, but now I am happy. I know I am working well and I am happy to be with my team-mates who are helping me as I am adapting to the Italian league.”
Juve did not threaten in the first half at Turin's Allianz Arena, while Ferrari had a header saved by Wojciech Szczesny, who also denied Alfred Duncan on 75 minutes. The keeper was beaten when substitute Khouma Babacar headed home in stoppage time.
Juve winger Douglas Costa came on in the second half and was red-carded after video review for spitting at an opponent in stoppage time.
Elsewhere, Genoa beat 1-0 Bologna, who had Erick Pulgar sent off in injury time, and Udinese and Torino drew 1-1.
Earlier in Rome, Roma squandered a two-goal lead in a 2-2 draw with visiting Chievo to slip seven points behind Juventus.
In stifling noon heat at Rome's Stadio Olimpico, Stephan El Shaarawy turned in a cross from Alessandro Florenzi, and Bryan Cristante profited from an Edin Dzeko assist to put Roma ahead. But Valter Birsa's great swerving shot and a Mariusz Stepinski clinical drive levelled matters in a hard-fought second half.
The Giallorossi inched onto five points, two behind Sassuolo, who are third on seven. Chievo have minus one point after being docked three last week in a trial for irregular bookkeeping.
Napoli have nine points after edging Fiorentina 1-0 Saturday, while Inter Milan (4) lost 1-0 at home to Parma and Sampdoria crushed Frosinone 5-0.
Empoli v Lazio and Cagliari v AC Milan play later Sunday. Spal v Atalanta completes matchday 4 Monday.