In an unprecedented day of sales, the UFC sold 42,000 tickets for its UFC 129 event, which will be held April 30 at Rogers Centre in Toronto.
The total was considered 'presale' tickets, or tickets made available only to those in the UFC fan club. Tickets to the general public do not go on sale until Saturday.
UFC officials had predicted the event likely would set records in attendance and revenue for a North American MMA event and are prepared to open up additional seating at Rogers Centre.
The venue has held more than 60,000 in the past; however, it's expected the total number of seats made available for UFC 129 will not exceed much more than 50,000.
"We don't take anything for granted," said Tom Wright, UFC Director of Canadian operations. "We did a lot of homework. We've spent literally weeks and months figuring out how to best configure this stadium. We're making this jump from arena to stadium and we didn't leave anything to chance."
The current all-time attendance record for a North American MMA event is 42,757, set by a K-1 Dynamite!! card in June 2007, despite evidence that much of that attendance came from unpaid tickets. The top-attended card in UFC history is UFC 124, which drew 23,152 in December in Montreal.
Wright said the UFC has tried to limit brokers from getting their hands on tickets.
"There's no way to track that but we do our best to make sure our tickets get in the hands of our fans," he said. "You can only buy a limited amount. It's not like you can get online and buy 200 tickets. Every individual order is capped to a certain number. That certainly wasn't the situation we wanted to happen where there would be a secondary ticket market."
UFC 129 will be headlined by two title fights, both featuring Canadians. George St. Pierre looks to defend his welterweight belt against Jake Shields, and fellow Canadian Mark Hominick faces current featherweight champion Jose Aldo.
"I think we're going to find that this is the best experience fans have ever had," Wright said. "The No. 1 objective Dana [White] and Lorenzo [Fertitta] set was making sure that the fan experience was in no way compromised. I believe we've enhanced it for this fight."
Brett Okamoto covers mixed martial arts for ESPN.com.