A day after Brazil's humbling 7-1 loss to Germany in the World Cup semifinals, Bach also said he is confident Brazilians will get over their "day of mourning" and fully embrace the first Olympics to be held in South America.
Bach and the IOC executive board received an update from Rio organizers, whose preparations have been dogged by severe construction holdups. In April, the International Olympic Committee enacted emergency measures to get the games on track, assigning a senior troubleshooter to work with local organizers and setting up a special task force.
Since then, Bach said, the Brazilians have heeded the message.
"We can really see there is a great dynamism in their preparations," he said at a news conference at the close of the three-day board meeting. "In particular, the city of Rio and the mayor and the governor have taken action on the government side and are making progress with regard to different venues."
However, Bach again warned that Rio is facing extremely tight deadlines.
"We have to stay vigilant and there is still no time to lose," he said. "But you really feel the determination and the enthusiasm of the organizing committee and their partners."
Bach cited the start of construction last week on the Deodoro site, a complex for 11 Olympic sports, as well as progress on the main media centre and anti-doping lab.
"It's now about the venues," he said. "We need to keep this dynamism. It's about getting the venues ready in time for the test events."
Bach was flying later Wednesday to Rio, where he will attend Sunday's World Cup final. On Friday, he will meet with Brazilian President Dilma Rousseff to discuss the Olympic preparations.
"We are very confident we will have a great games in Rio and the sports-loving Brazilians with all their enthusiasm will be wonderful hosts," Bach said.
Brazil's World Cup preparations were marred by severe delays, with some stadiums finished at the last minute. But the tournament has run smoothly without major organizational problems.
"We're very happy that many of the concerns which were mentioned before this World Cup did not turn into reality," Bach said.
With billions of dollars being spent on the World Cup and Olympics, there have been concerns that both events could be the target of massive protests. However, Bach said Rio organizers presented figures showing strong public support.
"The World Cup and the organization and the atmosphere is clearly supporting the organization of the Olympic Games," Bach said.
He dismissed suggestions that the host nation's humiliating defeat to Germany on Tuesday night would spoil Brazil's enthusiasm and goodwill for the Olympics.
"I can fully understand that today maybe in Brazil there will be this day of mourning," said Bach, who watched the match on a big screen at a Lausanne hotel, sitting next to Rio organizing head Carlos Nuzman. "But the Brazilians are very optimistic people and they know that after each defeat there is a new victory waiting for you. I'm sure they will grasp this opportunity."
On a separate issue, Bach said the IOC is reviewing its ticketing system for Rio in the wake of a scandal involving the illegal re-sale of hospitality tickets at the World Cup. Four companies were implicated and an executive of the MATCH group, which has the rights for the World Cup hospitality program, was arrested for questioning.
Several Olympic officials were accused of selling their tickets on the black market before the 2012 London Games, prompting the IOC to tighten its rules.
"We will take the necessary decisions if any are needed," Bach said. "We have a system in place. This system has been improved after London but it's under constant monitoring because it has to be adapted to the national legislation in the host country."
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