AMA Pro Racing and its competitors will have to abandon their long-established grid formation of four riders on each staggered row and use the same three-wide grid setup used by the FIM Grand Prix World Championships during this coming weekend’s Red Bull U.S. Grand Prix at Mazda Raceway Laguna Seca and during the August 26-28 Red Bull Indianapolis Grand Prix at Indianapolis Motor Speedway. The news came within the AMA Pro Racing’s supplemental regulations, which were issued to credential holders today, as they are preceding each round of the series. A call to AMA Pro Road Racing Race Director David McGrath confirmed the new setup is going to happen. McGrath said he was informed by Mazda Raceway Laguna Seca personnel that if a four-by-four grid was marked onto the front straightaway of the track it would not pass inspection by Claude Danis, the FIM official in charge of inspecting and homologating racetracks.