- The 34-year-old netted from the penalty spot in the 91st minute after Davide Calabria was adjudged to have handled in the area.
- The strike was his 24th of the season in all competitions for Juve, 12 of which have come since the turn of the year.
- Maurizio Sarri's side meet Milan again for a place in the final on March 4.
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The 34-year-old's goal was a controversial 91st minute penalty after Davide Calabria was adjudged to have handled the ball in the box.
The Milan defender, who had his back turned, saw Ronaldo's attempted overhead kick ricochet off his elbow. Referee Paolo Valeri consulted the video assistant referee (VAR) and reviewed the incident pitchside, before pointing to the spot and awarding Calabria a yellow card, much to his dismay.
Ronaldo then thumped home from 12 yards to cancel out Ante Rebic's 61st minute opener and send the two sides into the second leg with the scores level.
AC Milan manager Stefano Pioli said he was "angry" with the decision, according to Goal .
Ronaldo, meanwhile, extended his excellent run of scoring for Maurizio Sarri's side. The Portuguese international has now scored 24 times for Juve in all competitions, with 12 of those goals coming since the turn of the year.
On Sunday, he netted for the 10th consecutive Serie A match as Juve suffered a shock defeat to Hellas Verona, meaning he is now just one off equaling the Italian top division's best ever scoring run. Both Fabio Quagliarella and Gabriel Batistuta managed 11 in a row during the 2018/19 and 1994/95 seasons respectively.
Juventus and Milan will meet for a place in the final on March 4.
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