Rodrigo Messi, brother of the Argentine great was said to have been hit by a fan due to a heated exchange.
The family of the Barcelona star was rushed to a television cabin at the stadium for safety reasons, according to the report.
Messi, scored his team’s only goal in the penalty shootout but had a lacklustre performance overall.
This comes less than a year where he led and failed to lift the World Cup trophy and will potentially ignite criticism by those who say Messi doesn’t play as well with the national team as he does with his club.
Messi didn’t play well in the start of the Copa America but was improving match after match. He was coming off a remarkable performance in the 6-1 rout of Paraguay in the semifinals, when he didn’t score but helped set up five goals.
The next chance Messi will have to win a title with Argentina is in next year’s centennial Copa America in the United States. Before that, the 31-year-old playmaker will help his nation in qualifying for the 2018 World Cup in Russia.