The NFL game to be played at the new Wembley Stadium on 28 October is already guaranteed to be a sell-out.
Wembley is due to open this Spring
Around 160,000 fans requested more than 500,000 tickets in just three days following last Friday's pre-Super Bowl confirmation of the teams and venue.
Miami will face the New York Giants in the first regular-season NFL game to be staged outside of the Americas.
"Nearly all the requests have come from UK-based fans," said NFL UK managing director Alistair Kirkwood.
"These figures do not take into account the allocation of tickets for Dolphins and Giants fans from the US.
"So we anticipate a very quick sell-out when tickets go on sale in early March."
Wembley is expecting to seat between 85,000-90,000 for the game.