 Complete the following phrase:  In 1957 Fangio returned to Maserati, who were still using the same iconic 250F which Fangio had driven at the start of 1954. Fangio started the season with a hat-trick of wins in Argentina, Monaco and France, before retiring with engine problems in Britain. He also won the 12 Hours of Sebring sportscar race in America driving a Maserati 450S with Jean Behra for the second year running. But at the Grand Prix after Britain, the 