International Olympic Committee (IOC) officials insist they have "absolutely no regrets" about awarding the Games to Rio de Janeiro despite the organisation's vice-president John Coates admitting they are the "most difficult...we have ever encountered".

Almaz Ayana provided the opening session of the Rio 2016 athletics programme here with a historic flourish as she took more than 14 seconds off the world 10,000 metres record which has stood, apparently invulnerable, since 1993, claiming the first track and field gold of the Olympics in a time of 29min 17.45sec.