The tie with struggling Los Che did not get off to a good start for Ronaldo and his team-mates, with Simone Zaza and Fabian Orellana putting the home side 2-0 up within 10 minutes.
Ronaldo marked his milestone with a goal before the break, however, getting ahead of Eliaquim Mangala to meet a Marcelo cross with a powerful header that beat Diego Alves.
700 - Cristiano Ronaldo will make his 700th club appearance in this game (all competitions). Milestone. pic.twitter.com/ZalWJVLwmb— OptaJose (@OptaJose) February 22, 2017
However, he arrived at the club already one of the best players in the world, having lifted the Premier League crown three times, as well as the Champions League and Club World Cup once each in six years at Man United.