The 40-year-old, a London 2012 Olympian and part of the quartet beaten by United States in Toronto last month, had ridden Coronel MCJ into a slim lead following yesterday's 3.2 kilometres long cross-country event.

After his closest rival Marcelo Tosi knocked five-fences down on Glenfly in today's showjumping finale, Jorge began his test knowing he would would be able to dislodge four fences and still win. 

He did not need that cushio, however, as a superb clear round to end on 44.50 penalty points and win comfortably from Marcio Appel on 63.30, with Tosi, who had led after the dressage on another mount in Briefing DB Z before that horse was withdrawn, having to settle for third.

The event was misleadingly billed as the "Aquece Rio International Horse Trials", even though the field consisted of just 13 Brazilian riders, down from the initial expectation of 35.

Jorge's team-mate Ruy Fonseca, winner of an individual Pan American Games bronze medallist in Toronto, was another late withdrawal after his horse was declared unfit.

Various reasons were given for the absence of international riders, including the cost of sending athletes and horses, as well as concerns of a possible health risk following several reported cases of Glanders disease in the local area.

Organisers have since installed a full contamination zone to mediate against this risk.

Jorge dismissed any notion, however, his victory had been straightforward given the lack of top-level competition.

"The cross country was not an easy course and the showjumping was the same, so I am happy I didn't have any fences down," he said.

"I don't think it was easy, it was a good competition."

Representatives from 16 leading equestrian nations have been here for an observer programme held alongside the test event.

The feedback they gave after an inspection of the cross country course yesterday was largely positive.

Australia's Beijing 2008 team silver medallist Clayton Fredericks, now coaching the Canadian team, said how the course is in a "very good state", with "plenty of coverage of grass and the ground in good order". 

Dutch coach Marius Lips added: "The footage is very good and there is irrigation everywhere, so they can keep it to the right level. 

"There is a lot of space.

"When the flags are up for the Games, it will be beautiful here."

Concerns were raised however about journey times between the course here close to the Deodoro Olympic site and with the Athletes' Village in the main Olympic site in Barra de Tijuca, more than 20 kilometres to the south, particularly if the road is not improved before the Games begin.

"It has to be finished," said The Netherlands performance director Antonious van der Headen.

"It will be chaotic if not."

More work is still required to the venue here before the Games begin, including the rennovation of 180 stables and the installation of cabling and other infrastructural groundwork, although officials are confident all of this be done well in time.

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