Buenos Aires - Argentine football great Diego Maradona is to have treatment in Buenos Aires on an injured shoulder that forced him to miss a trip to the Cannes Film Festival where a documentary on his life was aired.

The 58-year-old, currently the coach at Mexican team Dorados de Sinaloa, wrote a message on social media late on Tuesday saying: "I'm in Buenos Aires, on the way home."

British director Asif Kapadia, who made the film on the Argentine icon, said on Sunday Maradona would need surgery.

Local media say he will stay in Argentina for around 10 days before returning to Mexico, where his employers are waiting for him to sign a contract extension.

The former Barcelona and Napoli player previously underwent an operation on his left shoulder in March 2017 in Dubai, where he was coaching the United Arab Emirates second division side Fujairah SC.

While back in his homeland, Maradona took the opportunity to express his support for beleaguered center-left former president Cristina Kirchner, just five months out from presidential elections.

Kirchner was in court on Tuesday for the opening hearing of a corruption trial in which she is accused of having favored a businessman friend in the attribution of public works contracts during her 2007-15 presidency.

She is the subject of a dozen corruption investigations.

The 66-year-old caused a surprise last week in announcing her intention to run for vice president having asked her former cabinet chief Alberto Fernandez to seek the top job in the October 27 poll.

She had been leading some opinion polls ahead of current President Mauricio Macri.

"Very happy with the news that Alberto Fernandez will be our new president, thanks to the GREAT Cristina," said Maradona.

The man best known for his "hand of God" goal against England in the quarter-finals of the 1986 World Cup, which Argentina went on to win, is a staunch supporter of left-wing politicians in the region.

He was friends with the late Fidel Castro and even has a tattoo of the former Cuba supremo on his left leg.

He was a supporter of late Venezuela president Hugo Chavez, as well as his successor Nicolas Maduro, and attended the funeral of Kirchner's husband Nestor, who was Argentina president before his wife.