Ronaldo, 37, failed to impress after being handed a rare start this season in Thursday's Europa League match in Cyprus.
United were given a huge scare when they went behind to a first-half strike from Karim Ansarifard but goals after the break from substitutes Marcus Rashford (2) and Anthony Martial turned the match on its head.
A late goal from Nikolas Panayiotou set up a nervy finish for the visitors but United held on to win 3-2 away from home.
It was a frustrating evening for Ronaldo, who had hoped to score his 700th goal in club football after bagging his 699th against Moldovan side Sheriff Tiraspol in the Europa League last month.
But he looked out of sorts throughout the match and struggled to hide his anger after missing several chances.
Midway through the first half, he fired a free-kick well over the bar to jeers from the home support.
He also failed to score with a header from close range minutes later, although he would have been flagged for offside had he put the ball in the net.
After the break, Ronaldo fired a shot into the side netting, angrily punching the air after seeing his effort go wide of the post.
He had another chance shortly afterwards but failed to connect properly with his shot, directing it well over the bar from a promising position in the box.
With around 15 minutes to go, Ronaldo had a huge chance to score his landmark goal after being set up eight yards out.
But he could only fire his shot against the post to the disbelief of United fans on social media.
"I was defending Ronaldo but not anymore. I’m afraid he's finished," wrote one fan on Twitter.
Another added: "How did Ronaldo not score there. Just wow…"
How did Ronaldo not score there.— Unknown African Breed 🇹🇿🇿🇲🇲🇼 (@name_is_mwizaso) October 6, 2022
Just wow ......🤦🏾♂️
How has Ronaldo not scored there... He's being made to work for Number 700 #MUFC— Rio 🔰 (@Rio_F79) October 6, 2022
Ronaldo is so so finished fam 🤦♂️— Beezy (@Beezy20011) October 6, 2022
"Malacia, Sancho, Ronaldo and Casemiro are USELESS," wrote another.
A fourth wrote: "It's sad to see this version of Ronaldo."
While another simply put: "Ronaldo is finished."
In the final moments of the match, Ronaldo had one final chance to score but could only curl his shot wide of the post.
His goalless performance means he has now scored just one goal in his nine appearances for United this season.
Featured Image Credit: BT Sport
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