Messi, 39, delivered one final masterclass in Argentina's blue and white on Tuesday, scoring once and setting up two goals in a 3-0 friendly win over Benin before more than 85,000 fans at Buenos Aires' Monumental Stadium, where his farewell became a celebration of an extraordinary 21-year international career.
"Yesterday was my last game, and I already miss wearing the blue and white. I know I'm making the right decision," Messi said in a lengthy Instagram post. "It's been an incredible journey, full of joy and also some sadness, but I know for sure that every step I took was worth it...
"I don't want to forget Diego (Maradona), who put our country where it deserved to be and who, as I always say, I know helped us both by being here with us and also from heaven, with every step we took.
"Thank you to the clubs where I played, for always respecting my feelings and allowing me to dedicate myself to my country whenever it was time to put on the national team jersey..."
Messi captained Argentina to the 2022 World Cup title and Copa America triumphs in 2021 and 2024, while also helping them win the 2022 Finalissima.
"I am grateful. I love you all very much; I'm going to miss you, and I will always thank you for having been by our side, by my side," the Inter Miami playmaker added.
Messi and Ronaldo have vied for recognition as the greatest player of their generation throughout their illustrious careers, with the 41-year-old Portuguese forward among those to respond to the post.
"Leo, after so many years of defending your country, you've made history that will last forever. I have the utmost respect for what you've accomplished with Argentina. A hug," Ronaldo said.
Ronaldo, meanwhile, is embroiled in a dispute with Portugal coach Jorge Jesus following his abrupt departure from the national team's training camp.