Eden Hazard's struggles at Real Madrid have been well-documented, and the challenges faced by the Belgian only serve to emphasise the size of Cristiano Ronaldo's achievements in the Premier League.
Current Chelsea man Saul Niguez has a theory as to why Hazard has found things tough in Spain. pointing to the differences between the Premier League and La Liga, and even Lionel Messi has had a tough time since leaving Barcelona for Paris Saint-Germain.
Ronaldo has had no such issues on a personal level, though, leading the goalscoring charts for Manchester United in his first season back.
