A congenital heart ailment that had gone undetected in numerous physical examinations killed star 27-year-old Ecuador striker Christian Benitez, the national team's physician said Friday.

Dr. Patricio Maldonado said a second, 2 1/2-hour autopsy performed after Benitez' body was flown home from Qatar found that the athlete died due to problems "that cannot be detected even with very sophisticated exams."

"Medical science is not 100 per cent effective," said Maldonado, "and we are left with painful incidents such as this."

The 27-year-old player died Monday in Qatar, a day after playing his first game with the El Jaish club. He had been admitted to the hospital with severe stomach pains after the match.

Benitez joined El Jaish last month after spending several years in Mexico, where he helped America win the Mexican championship last season.

Maldonado reminded reporters that Benitez had passed through a number of clubs where medical checkups are mandatory, "but this problem was only detected post-mortem."

The president of Ecuador's soccer federation, Luis Chiriboga, attributed the problem to a flawed coronary artery.

Thousands of people filed past Benitez' casket on Friday in the Ruminahi sports arena in the capital before a funeral service in which relatives and fans wept inconsolably for the one of the biggest stars of Ecuadorean soccer.

Benitez began his career with Ecuador's El Nacional club and later played for Santos and America in Mexico. He was briefly with Birmingham City in England.

He played for Ecuador's 2006 World Cup team and looked to be on his way to participation on the squad in next year's World Cup in Brazil.