RIO DE JANEIRO -- Former UFC middleweight champion Anderson Silva has withdrawn from his scheduled fight against Uriah Hall of Jamaica on Saturday in the city of Curitiba in southern Brazil.

Organizers of the event did not provide details for the 41-year-old's decision, and said Hall will not face a different opponen.

The main fight of the card will be between heavyweight champion and home crowd favourite Fabricio Werdum and American Stipe Miocic.

Silva, who is considered the greatest mixed martial artist in the young sport's history, has recently faced a series of problems.

Since 2015 the Brazilian has struggled with injuries and tested positive for banned drugs.