SAO PAULO: Former Chelsea midfielder Oscar is in stable condition in hospital after falling ill with a heart issue, his club Sao Paulo has said.

Brazilian media reported that Oscar was doing tests on an exercise bicycle when he collapsed and was unconscious for about two minutes.

The 34-year-old was then taken to hospital in an ambulance.

“During tests carried out on Tuesday morning, at SuperCT, as part of pre-season preparation, athlete Oscar presented a complication with cardiac changes, and was promptly treated by the club's professionals and the medical team from Einstein Hospital Israelita, who were present at the scene,” Sao Paulo said in a statement.

“The player was then taken to the hospital, where he is clinically stable and remains under observation for further tests to clarify the diagnosis.”

Oscar has a contract with Sao Paulo until 2027. He returned to his boyhood club on a free transfer last December after a long spell in China.

Oscar won one Europa League title and two Premier League trophies with Chelsea, which he joined in 2012.

He moved to Shanghai in the middle of Chelsea's 2016-17 season for a transfer fee reported to be $73 million. He won three Super League titles in China and became a fan favorite in Asia.

Oscar played for Brazil at the 2014 World Cup where he scored the only goal in its 7-1 semifinal defeat to Germany, which went on to win the tournament.