FIFA has ordered bone tests to be performed on players at the Under-17 World Cup in Nigeria to catch teams who have picked ineligible over-age players.
Football's global governing body said it would conduct the magnetic resonance imaging (MRI) tests “to protect the integrity of the tournament and in the spirit of fair play.”
The decision follows reports from Nigeria that the host nation hoped to select a number of players for the October 24-November 15 finals who were too old.
Nigeria, which is the defending champion, has a tradition of success at world age group tournaments but has been dogged by rumours that it has fielded over-age players.
FIFA said MRI tests on wrist bones had been developed by its medical research center which allow it to determine the age of players.
“MRI of the wrist can identify players who are definitely above 17 years,” FIFA said in a statement.
“It is reliable, evidence-based and safe for the player.”
Players from the 24 competing nations – which include Brazil, Iran, Japan, Spain and the United States – will be randomly selected for testing.
FIFA said it encouraged the 24 teams to conduct their own tests to ensure all players comply with the age rule.
Tournament regulations state players must be born on or after January 1, 1992.