Cheerleaders, a pre-game “tailgate” barbecue and post-game interviews in the locker room: London’s Wembley Stadium becomes a little corner of the US on Sunday when the Miami Dolphins play the New York Giants, the first regular-season National Football League game to be played outside the Americas.

For all the preparation, Mark Waller, the NFL’s head of international development, is still unsure how the sellout 80,000 crowd and UK television audience will react to this latest attempt to export a US sport.