FIFA may not be able to fully test the Sao Paulo stadium with a capacity crowd before the World Cup opener in two weeks.
Only 40,000 tickets are being sold for Sunday's Brazilian league match being played at the venue because sections of temporary seats recently installed have not yet been certified by local building authorities.
FIFA wanted the stadium tested at full capacity at least once before nearly 70,000 people arrive for the tournament opener between Brazil and Croatia on June 12.
The temporary seats also weren't used in the first official test event at the Itaquerao earlier this month, when less than 37,000 people attended.
FIFA made an exception to have a match played so close to the tournament because it was deemed necessary to properly evaluate the stadium.
FIFA secretary general Jerome Valcke last week said it was "vital" to test all Itaquerao facilities "under full match conditions, including the temporary seats."
FIFA said another test at the stadium was important "given the attention drawn from the opening match," when many heads of state will be among the special guests.
Confirmation that only a portion of the seats would be put on sale was announced by stadium owner Corinthians late Thursday. The club did not obtain the needed clearances from local authorities to allow a full crowd.
FIFA did not immediately comment on the change, but the local World Cup organizing committee said in an email that it was still hoping to fully test the venue.
"The idea is to use the temporary stands in the test match between Corinthians and Botafogo on Sunday, but that will depend on the needed technical clearances," the committee said, adding that Corinthians was responsible for obtaining the clearances from local safety authorities.
The second test event at the Itaquerao was originally scheduled for Thursday, but local authorities said the match would have disrupted the city's "operational routine" on a working day.
Local organizers admitted there were problems in the first test match on May 18, including a leaking roof, but said overall they were satisfied with how the venue held up.
Valcke on Thursday finished a tour of all 12 World Cup host cities to check on preparations one last time. During his two-week trip, he expressed his concern about work in Porto Alegre, Natal and Sao Paulo, but said he was mostly satisfied with the other nine cities.