The 2005 United States Grand Prix was one of the most controversial Formula One motor races in modern history. It was held on June 19, 2005 at the Indianapolis Motor Speedway. It was the ninth race of the 2005 Formula One Season. Out of 20 cars entered for the race, only the six cars from the teams using Bridgestone tyres (Ferrari, Minardi and Jordan) competed. The remaining fourteen entrants, all using Michelin tyres, retired after the parade lap due to safety concerns. Following several tyre failures before the race, most spectacularly on Ralf Schumacher's Toyota during Friday practice, Michelin advised its seven customer teams that the tyres provided for the race were not safe to use for the entire race, even though they had been providing working tyres for the race since 2001. The situation was worsened by the 2005 Formula 1 rules, which forbade tyre changes during the race; and also by a resurfacing of the circuit, which resulted in greater tyre wear.