Uruguayan defender Guillermo Varela and Brazilian midfielder Gerson traded punches Tuesday during a training session at their club, Flamengo, the latest violent episode for Brazil's most popular football team.

Flamengo confirmed there had been an "altercation" between Varela, 30, who once played for Manchester United, and Gerson, 26, formerly of Roma and Marseille.

"The altercation between Gerson and Varela was resolved internally," the Rio de Janeiro club said in a brief statement on social media.

Brazilian sports news site Globo Esporte reported the fight started when Gerson fouled Varela during training. The two internationals got into an argument, which escalated into an exchange of punches, it said.

Varela suffered what may be a broken nose, newspaper Estado de Sao Paulo reported.

It is the second violent incident in just over two weeks at Flamengo.

On July 29, physical trainer Pablo Fernandez punched Pedro, one of the club's most popular players, after the Brazilian international reportedly ignored his orders to warm up for a match.

After the incident, Flamengo sacked Fernandez, formerly coach Jorge Sampaoli's right-hand man.

Flamengo have been struggling in recent weeks, amid reports some players are unhappy with Argentine Sampaoli's management.

Their Copa Libertadores title defense was cut short last week when Paraguayan club Olimpia came from behind to knock them out in the round of 16 (3-2 on aggregate).

Flamengo are currently fourth in the Brazilian league, trailing surprise leaders Botafogo, their cross-town rivals, by 15 points.