SAO PAULO (AP) — Brazil arrives at a crucial moment in its preparations for the World Cup as two of its most troubled stadiums stage major test events Sunday.

With FIFA closely monitoring, local organizers will host Brazilian league matches at the Arena Pantanal in the western city of Cuiaba and at the Itaquerao, Sao Paulo’s much-delayed stadium where the World Cup opener will be played in a few weeks.

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Although there will still be work left at the venues no matter what happens Sunday, successful tests could help alleviate concerns about the country’s readiness for the event.

The official test events are likely the last before all 12 World Cup stadiums are turned over to FIFA for their final preparations ahead of the June 12 inaugural match between Brazil and Croatia.

The Itaquerao has proved the most problematic stadium and one of FIFA’s biggest concerns, especially because it will have to accommodate the nearly 70,000 fans and guests coming for the high-profile opener.

Only 40,000 tickets were put on sale for Corinthians’ match against Figueirense because some of the 20,000 temporary seats needed for the opener are still being installed.

“I’m confident the test event will be successful,” said Ricardo Trade, chief executive of the local World Cup organizing committee. “I have no doubt. The Corinthians stadium is one of the most refined stadiums, it has one of the best pitches.”

Corinthians players practiced at the Itaquerao on Saturday surrounded by workers trying to get the venue ready for the match.

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The stadium is where a huge crane collapsed last year, killing two workers and causing significant damage at the site. Earlier this week, prosecutors threatened to halt work because of health and safety issues at the site, and on Friday the construction company in charge of the venue said the stadium’s roof will not be fully finished in time for the World Cup.

FIFA will take over the Itaquerao next week so it can adapt the venue for the opener. In all venues, the installation of the temporary structures needed to accommodate sponsors, media and technical teams are likely to remain underway until just days before the tournament begins.

The Arena Pantanal will host the match between Santos and Atletico Mineiro in its final test on Sunday. The venue already hosted an official match in April, but only half of the seats had been installed at the time. The venue’s inauguration was delayed several times.

The Arena da Baixada in the southern city of Curitiba is the other stadium yet to be completed. The venue underwent its first and final test event during an exhibition match on Wednesday. Organizers acknowledged there were problems but said they were mostly pleased with the result. Seats are still being installed at the stadium, which was nearly excluded from the tournament earlier this year because of chronic construction delays.

On Saturday, the local World Cup organizing committee successfully held a test event in Brasilia’s Estadio Nacional, one of the six stadiums built for last year’s Confederations Cup. Nearly 30,000 attended the match that marked the final of the local championship.

FIFA wanted the other six venues ready by the end of last year so they could be fully tested, but none were completed in time. Football’s governing body usually wants three test matches at venues before tournaments such as the World Cup. This time, some won’t be tested at all with a full crowd.

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