New Zealand rugby star Sonny Bill Williams was reportedly forced to wait nearly 90 minutes for an ambulance after being injured because the driver was lost as IOC vice-president John Coates described Rio 2016 as the "most difficult" the International Olympic Committee has organised.

Williams suffered a ruptured Achilles’ tendon during the second half of New Zealand’s surprise 14-12 loss to Japan on Tuesday. However, after the driver could not find his way to the Deodoro rugby stadium, Coates revealed the problems the 31-year-old had in reaching the hospital was an indication of the issues they were facing.

“It’s still difficult,’’ Coates told the Daily Telegraph in Australia. “Every morning we have a meeting with the IOC president and vice-presidents and each of the federations and Olympic committees and we also meet with the organising committee.

“But transport, there’s still incidents. The Olympic lanes are working well for the athletes.

“But Sonny Bill with the Achilles’ [injury] yesterday, the ambulance didn’t know where to go and so it took an hour and a half. Luckily it was an Achilles’ and not concussion.’’

In April 2014, Coates – a lawyer who is also president of the Australian Olympic Committee – compared Rio's preparations unfavourably with the notoriously last-ditch 2004 Olympics in Athens, amid rising concern about the rush to finish competition venues and associated infrastructure.

Unrest

After five days of competition, there have been a number of incidents mainly caused by political and economic unrest in

Brazil

. The Olympic torch was attacked as it arrived in the city last week, while there have been a number of other security issues, including an attack on a media bus and a stray bullet being fired into the roof of the equestrian media centre.

Speaking on the BBC’s Today programme, Coates admitted it had been a testing Olympics so far. “It’s been very difficult, the most difficult Games we have ever encountered in terms of political and economic background,” he said.

“Seven years ago when [Rio] were selected, they were on the verge of being a top five GDP nation in the world. They’re 74th now and it’s been a struggle.”

Coates also denied reports that a bus used to transport media had been hit with bullets, blaming the incident on rocks being thrown.

Secure

“Of course, it is [a concern]. You want everyone to be secure and everyone that’s here to cover the games or play in the games, so I’m sorry to hear that,” he said.

“Signage is still a big issue in places like Deodoro. A few days ago, hockey spectators were getting off a train and taking the wrong route and walking four kilometres and missing their game.”

“But I’d have to say that the issues of a morning are much less now and we’re getting there.’’ Guardian Service