Leaders Al Hilal moved seven points clear of their closest rivals as a late Aleksandar Mitrovic double came after Sergej Milinkovic-Savic's opener.
Home side Al Hilal took the lead in the 64th minute, but there was plenty of drama between that and Mitrovic's brace.
Ronaldo thought he'd scored the equaliser in the 73rd minute, but his stunning first-time volley was just offside, something the 38-year-old furiously disputed.
Then with five minutes to play, Ronaldo lept for a Sadio Mane cross, and got caught up in an almighty tumble.
Morocco hero Yassine Bounou came out to punch the ball clear, but completely missed and ended up on top of Ronaldo.
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The Portuguese rolled around in agony, and although replays showed the original punch didn't make contact, it did appear Bounou came down on his head after.
That was backed up by the former Real Madrid superstar sporting a swollen bottom lip, needing treatment before repeatedly shaking his head at the referee.
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