Ronaldo curled in the opener after just two minutes in Turin, adding a second from the penalty spot after 66 minutes, putting the Portuguese top of Serie A’s scoring charts with 14 goals.
Fabio Quagliarella pulled Sampdoria level with a penalty after 33 minutes, with the visitors having a late Riccardo Saponara goal ruled offside after consultation with the video assistant referee.
Juventus open up a 12-point lead at the top of Serie A ahead of Napoli who can reduce the gap when they host Bologna later on Saturday.
The seven-time reigning champions also have a record number of points before the three-week winter break with 53 from 19 games.
“The team is doing very well, we had an excellent first half to the season, now we have to keep working to ensure we keep this form in the second half of the season,” Ronaldo told Sky Sports Italia.
“I like VAR because these are difficult decisions for a referee and we should welcome anything that makes his job easier.”
The reigning champions have dropped points just twice this season, being held by Genoa at home and 2-2 against Atalanta midweek, and are firmly on track for an eighth consecutive Scudetto.
