He officiated his first senior international match on 5 June 2015 between Chile and El Salvador.
[12][13] In March 2019, he was selected a referee for both the 2019 FIFA U-20 World Cup in Poland and the 2019 Copa América in Brazil.
[14][15][16] As part of a referee exchange programme between CONMEBOL and UEFA, Rapallini was selected on 21 April 2021 as a referee for UEFA Euro 2020, to be held across Europe in June and July 2021.
[17] This marked the first time a South American referee had been selected to officiate at the UEFA European Championship.
Rapallini was selected to be a referee at the 2022 FIFA World Cup, where he officiated three matches.