Ronaldo was the victim of two crunching fouls delivered by Chelsea flop Kalidou Koulibaly in the first half. Some Al Nassr players had to be held back after the second as Koulibaly struggled to contain the dangerous No 7.
CR7 picks up injury after heated outing
And tensions also flared after the referee awarded Al Hilal a penalty immediately after Ronaldo's equaliser, sparking a heated exchange with rival boss Jorge Jesus.
VAR correctly overruled the decision, though, and Ronaldo went on the have the last laugh.
However, Al Nassr will be concerned over their star man's fitness after he was carted off with a painful-looking injury in the 115th minute.
Peter Drury on inspiration for iconic Ronaldo commentary line
Cristiano Ronaldo proved he remains the most clutch footballer in history as he netted a brace to fire Al Nassr to a 2-1 win against Al Hilal in the Arab Club Champions Cup final. Al Nassr fought back from a goal down to seal Ronaldo's first piece of silverware since his Saudi Arabia switch.
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Ronaldo finally lifts Saudi silverware
Ronaldo's wait for silverware in Saudi Arabia is over after falling short in last season's Saudi Pro League and Kings Cup.
Ronaldo was Al Nassr's standout star, as he often is, and forced extra time with his 74th-minute leveller after Al Hilal's Michael mocked his famous 'Siu' celebration in the first half.
The 38-year-old thought he fired his side into the lead in the early stages of extra time before Ali Al-Boleahi produced an incredible acrobatic goalline clearance.
But his headed rebound moments later ensured he added to his illustrious trophy collection in the Middle East continues into the new league season.
Koulibaly puts on horror show
Koulibaly received a yellow card for his reckless challenges on Ronaldo, and his performance didn't improve much from there. The 32-year-old endured a nightmare season at Chelsea before his summer switch to Al Hilal.
And he failed to impress in the Arab Cup final, recording just 70 per cent pass accuracy, winning just two of his eight duels and making four fouls. The defender was even substituted midway through the second half.
Al Hilal will want improvement from their new £20m man if they are to challenge for the Saudi Pro League title this term.