Should he bag a hat-trick, like he did against Tottenham last month, the Portugal legend would officially record the most prolific campaign by any player in top-flight history after their 36th birthday.
The current record belongs to Zola, whose most lethal season at Stamford Bridge was his last: a 14-goal return at the age of 36.
While sixth-place United haven't fared well this season, getting knocked out of every tournament, Ronaldo is among the Premier League's top scorers with 12.
Against Tottenham in his last league match, Ronaldo became the highest goalscorer in the history of football thanks to a historic treble.
With the season coming to its conclusion, Man United still have a lot of work to do to qualify for the Champions League ahead of the 2022/23 campaign.
But Ronaldo's good form could help them get over the line, and for the Portuguese icon, breaking Zola's record in the process.
The Italian was loved at Chelsea in his seven-year spell, having helped them win two FA Cups and one League Cup.
He also played a huge role in the club securing qualification for the Champions League in 2002/03, which was a defining campaign.
Zola scored 14 goals and featured in every league game, which included the dramatic 2-1 win against Liverpool on the final day that saw the Blues pip the Reds for fourth.
Zola was indispensable, and proved that age is just a number, it also meant meant he is the highest scorer aged 36 or older.
But now Ronaldo, who is 37, could overtake him, and cement himself into another history book.