Argentina were set to stage the showpiece South American tournament, starting June 13 in Buenos Aires, following CONMEBOL's decision to strip Colombia of co-hosting rights due to anti-government protests and COVID-19 concerns in the nation.
However, Argentina will not stage the Copa America – already pushed back a year due to the coronavirus pandemic – as the governing body considers new hosts.
Messi and co., who finished third in 2019 following back-to-back runners-up performances in 2015 and 2016, were set to open the South American tournament against Chile in Buenos Aires on June 13.
Argentina will also face Uruguay, Paraguay and Bolivia in Group A and Messi is relishing the Copa America as the superstar captain seeks his first senior trophy with La Albiceleste.
"I'm very excited and eager, I'll try to do things right," Messi said on Sunday, with Argentina riding an 11-match unbeaten streak.
"In the last Copa America we left a good image, but we cannot stay with that and we will have to continue growing.
"The last qualifying games we did well too, although it's been a long time since those games and we couldn't get back together, we'll have to get back on track quickly and keep growing."
"I'm always excited to compete with the national team, whatever game it is, we always want to win, it's always the same goal," added the record six-time Ballon d'Or winner.
"The truth is that the youngest are eager and the oldest too, with the same or more eagerness. We are a very nice and united group with a good base that has already been working since [head coach Lionel] Scaloni started and some new ones who joined at the last moment. The important thing is to form a very strong group for the objectives that lie ahead."
Before their Copa America campaign, Argentina will meet Chile (June 3) and Colombia (June 8) in CONMEBOL World Cup qualifying.
The coronavirus pandemic has wreaked havoc with matches postponed, but before COVID-19 led to suspensions, Argentina had won three of their first four games to be two points behind Brazil in second spot.
"I'm happy to be here with all my colleagues. It is a strange and different situation from what we usually live in and we cannot live in a normal way, but little by little we are getting together and working for the two qualifying games because both will be very difficult.
"All qualifying games are very tough. Chile are a great team with very good players, although they have a new coach and he didn't have many games, they have very experienced players base and many kids who are up to the task. They had a generational change like us and they are growing and preparing, it is a very competitive team.
"We try to comply with all the recommendations they give us, the last qualifying matches we had were very similar to what we are experiencing now, although now it is more serious due to the situation in the country. Unfortunately we are having a hard time, there are many infected, so we are trying to accommodate ourselves and comply with what they tell us to do everything well."