The Argentine has played Real Madrid twice in the Champions League: 14 times in La Liga, five times in the Copa Del Rey and on four occasions in the Spanish Supercopa.
Ronaldo, meanwhile, has met Barcelona twice in the Champions League (not including the three times he played them in Manchester United colors), eight times in the league, five times in the Copa Del Rey and four times in the Supercopa.
Based on the numbers, Messi's record is clearly superior to that of the Portuguese, as he enjoys a winning percentage of 44 percent and an average of 0.72 goals per game, compared to Ronaldo's winning percentage of 26 percent and strike rate of 0.63.
The Barcelona No. 10 has also been far more prolific in assisting his teammates, setting up 10 more goals than his Madrid counterpart.
Ronaldo could (and probably would) argue that he has closed the gap somewhat in recent times, however, as in the last six games between the Spanish giants (including both legs of the Supercopa), he has scored six times to Messi's five.
The Argentina captain is currently tied with Alfredo Di Stefano as the all-time top scorer in El Clasico, while in October, 2012, Cristiano became the first player to score in six consecutive Barcelona-Real Madrid matches.
Let's take a look at the two players' statistics and focus on three of each player's most memorable Clasicos:
Messi's Record Against Real Madrid
Hat-Trick on Nou Camp Clasico Debut
March, 2007. What better way to announce your arrival to the Camp Nou faithful than to hit a hat-trick against Real Madrid?
Orchestrating the 5-0 rout
November, 2011. Messi is renowned for his goalscoring abilities, but in this match he was utilized in a deeper playmaking role. He duly wreaked havoc.
Champions League Semi-Final Golazo
April, 2011. In the biggest Clasico encounter in recent years, Messi stamped his class on the Champions League semi-finals with an excellent pair of goals. The second strike was unforgettably brilliant.
Ronaldo's Record Against Barcelona (for Real Madrid)
August, 2012. Madrid trumped Barcelona to the silverware this time around, with Ronaldo scoring a freakish goal to seal the deal.
At the Double
October, 2012. Cristiano nails a well-taken double to deny Barca a win and detract slightly from Messi's own double in the same match.
Everybody Calm Down
April, 2012. In arguably his finest Clasico moment, Ronaldo scored a 73rd-minute winner at the Camp Nou. It was Real Madrid's first win in eight league matches against their archrivals and sent Los Blancos on their way to their first La Liga win in four years.