The Real Madrid forward's strike in Wednesday night's quarter-final first-leg clash with Borussia Dortmund at the Santiago Bernabeu took his tally for the 2013-14 campaign to 14.
Ronaldo is now level with Messi, who netted 14 times in 11 games during the 2011-12 tournament.
Remarkably, the Portuguese has matched the Barcelona ace's tally in just eight outings this term, averaging a goal every 50.71 minutes.
No player has ever scored at such a rate in Europe's premier club cup competition.
Messi's average during his record-breaking 2011-12 season was a goal every 70.71 minutes, while Ruud van Nistelrooy was even more prolific during Manchester United's run to the quarter-finals in 2003.
The Dutchman netted 12 times in total, giving him an average of a goal every 57 minutes.
Given Ronaldo is scoring at an even better rate, and the fact that the injury that forced him off against Dortmund at the Bernabeu does not look serious, he will have the chance to take outright possession of Messi's record at Signal Iduna Park next week.