Rio Olympics 2016: Games organisers say crowd numbers 'look very promising'
Rio Olympics organisers say ticket sales for the remainder of the Games "look very promising".
Row upon row of empty seats were on show when the athletics events began in the Estadio Olimpico on Friday.
But officials claim 93% of tickets were sold for Saturday's morning session, and 79% for the evening.
"We'd rather celebrate the fact that the Olympic Stadium looks beautiful today with a full crowd," said Rio 2016 spokesman Mario Andrada.
"As we move forward into the second half of the Games, we see more and more people coming, more and more people enjoying the Games and more and more Brazilians bringing the energy to the Games.
"I think it looks very promising moving ahead."
Ticket prices, VIPs not filling their allocations and ticket holders only wanting to see one particular contest in a long session have been cited as reasons for the empty seats on Friday.
"We cannot regret something that we cannot fix," said Andrada, adding organisers were "not disappointed" by the sales.
Organisers say a total of 3,311,000 tickets have been sold across all venues since the Games started.
Rio 2016's organising committee has been criticised for the ticket-pricing structure, considering the country is in the midst of an economic recession.
It has denied high ticket prices have put Brazilian fans off, while the International Olympic Committee said prices offered to overseas fans were not too high.
"Without heroes and local athletes the public take longer to fall in love," Andrada said on Friday.
"But one of the legacies of the Games will be to show Brazilians how spectacular these other sports can be and there will be no problem when Usain Bolt competes on Sunday."
Jamaica's Bolt, 29, is attempting to win the 'treble treble' of 100m, 200m and 4x100m golds at three successive Olympics.
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