Tragedy struck on this day in 1994 at the San Marino Grand Prix when Brazilian Formula One driver Ayrton Senna da Silva was killed in a crash while leading the race. Senna has voted as the best and most influential Formula One driver of all time in numerous motorsport polls. From 1989 until 2006 he held the record for most pole positions. He holds a record six victories at the Monaco Grand Prix, and is the fifth-most successful driver of all time in terms of race wins. Senna courted controversy throughout his career, particularly during his turbulent rivalry with Alain Prost. In the Japanese Grands Prix of 1989 and 1990, each of which decided the championship of that year, collisions between Senna and Prost determined the eventual champion, which was Prost in both years. Senna’s death was considered by many of his Brazilian fans to be a national tragedy, and the Brazilian government declared three days of national mourning.