The $289 million (£180 million/€224 million) Arena Grêmio (pictured top) is the first of 14 new stadiums being developed ahead of Brazil 2014 and it was inaugurated with home side Grêmio securing a 2-1 victory in a friendly over Bundesliga club Hamburg SV.
But following the match, club officials said they are still unsure as to why the venue will not be used for the World Cup, with FIFA instead opting to stage games at the nearby Beira-Rio Stadium which is owned by Grêmio's arch-rival Internacional.
The Beira-Rio Stadium is currently undergoing a $159 million (£99 million/€123 million) redevelopment and it is not expected to be completed before December 2013.
"That [why the stadium will not be used for the World Cup] hasn't been explained to us," said Grêmio's vice-president Eduardo Antonini.
"We are the first stadium to be ready.
"This city is passionate about its football and instead the World Cup has gone to other places with less footballing tradition."
The Arena Grêmio is not the only new venue that has failed to make the World Cup list with Palmeiras' 45,000-seat stadium in São Paulo having a similar status.
Nevertheless, Grêmio's new home has received praise from Ronaldo, the Brazil 2014 member who led the country to victory at the 2002 World Cup.
"I've been in the best and most famous stadiums and the Arena is excellent," said Ronaldo, who is widely considered one of the best strikers in history.
"I've only seen stadiums like this in Europe and this is up there with the best in the world."
Experts believe that the Grêmio and Palmeiras' stadiums could be used as backup options by FIFA if any of the World Cup's 12 host venues fail to be ready on time.
"Nobody is talking about it but I think it [Arena Grêmio] is a Plan B," said Stochos sports marketing agency President Cesar Gualdani.
"The Palmeiras stadium too.
"If a World Cup stadium is not on time or has problems, they have these as alternatives."
Contact the writer of this story at [email protected]s.biz