Lautaro Martinez gave Inter an early lead but Ronaldo fired home a penalty before taking advantage of a defensive mix-up to give Juve the advantage in this tie.
Inter were missing two key players in Romelu Lukaku and Achraf Hakimi through suspension and looked blunt in attack as a result.
So which players stood out most in this Derby d'Italia?
✔️ GOOD PERFORMANCE
Matthijs De Ligt: 7.3
De Ligt only recently returned to full health following a spell out with Coronavirus but he is already close to top form again.
He marshalled the Juventus backline well, winning all three of his tackles and five of his six duels.
The Dutch giant also made a game-high six recoveries and four Interceptions in a powerful display at the back alongside Merih Demiral.
❌ BAD PERFORMANCE
Ashley Young: 5.4
Inter's left flank has been arguably their weak spot this season and it once again proved to be their downfall this evening.
With the Nerazzurri leading, Young lost Juan Cuadrado as he charged into the box to try and meet Federico Bernardeschi's cross. He then pulled the Colombian back three times, leaving the referee no choice but to award a penalty. Ronaldo converted with ease.
⭐ STAR MAN
Cristiano Ronaldo: 7.7
The Portuguese superstar is set to turn 36 on Friday but he is showing no signs of slowing down.
Ronaldo hit a first-half double to put Juventus into the driving seat of this tie. He equalised by firing a penalty straight down the middle of the goal. And then he put Juve ahead by pouncing on a mix-up between Alessandro Bastoni and Samir Handanovic and dispatching into the net from a tight angle.
As is usually the case, no one had more shots in this game than Ronaldo.
The ex-Real Madrid hero now has 21 goals in just 23 games for Juventus this season.