Mourinho has worked with some of the greatest players in world football but a solitary season spent with the two-time FIFA World Cup winner at Barcelona was enough to convince him of his incredible talent.
Mourinho worked as an interpreter to then-Barcelona manager Sir Bobby Robson in 1996 when Ronaldo was recruited from PSV Eindhoven for a world-record transfer fee of €19.5m.
Ronaldo set the Camp Nou alight, netting 47 goals in 49 appearances across all competitions as Barcelona won the Copa del Rey, Supercopa de Espana and the UEFA Cup Winners’ Cup in his only season at the club.
Cristiano Ronaldo and Lionel Messi are widely considered to be the best of their generation, sharing 10 Ballon d’or awards between them but Mourinho believes Brazil’s Ronaldo trumps them all when it comes to talent and skill.
"Ronaldo, 'El Fenomeno', Cristiano Ronaldo and Leo Messi have had longer careers, they have remained at the top every day for 15 years," Mourinho told LiveScore.
"However, if we are talking strictly about talent and skill, nobody surpasses Ronaldo [Nazario].
"When he was at Barcelona with Bobby Robson, I realised that he was the best player I'd ever seen take to the field.
"Injuries killed a career that could have been even more incredible, but the talent that that 19-year-old boy had was something incredible.
"In 1997, Barcelona played against PSG in Rotterdam and Ronaldo's goal, 1-0. Awesome."
Ronaldo, who retired in 2011, joined Inter Milan after leaving Barcelona before taking in further spells at Real Madrid, AC Milan and Corinthians.
