Monaco (2018–2026) against Spain (2015–2026)
The title count is dead even (0 apiece). The difference shows up elsewhere: Charles Leclerc was more dominant relative to their own era's competition, averaging 36% of the maximum possible points per season against 19% for Carlos Sainz Jr.. The rest just confirms the gap: Charles Leclerc also leads Carlos Sainz Jr. in win rate (4.9% against 1.6%), podium rate (29.2% against 11.9%), pole rate (13.0% against 2.1%), and reliability (14.1% against 18.5% in DNFs). They were also teammates (2021, 2022, 2023, 2024), so with the same car, and there the verdict is clear: Charles Leclerc finished ahead of Carlos Sainz Jr. in 51 races against 33.