As with the previous season, the number 0 car was driven by Damon Hill for the entire year. Only the defending champion had the right to use number 1 and reigning champion Alain Prost had left the sport. The number 2 car was driven by Ayrton Senna until he was killed at Imola. Williams test driver David Coulthard filled in for most of the season but Williams also brought back Nigel Mansell, who had won them the drivers' title for them in 1992, when his Indycar commitments allowed. Although it was fast, the car proved to be a tricky proposition in early testing and in the early part of the season. The car had a number of problems that were not properly remedied: a design flaw was discovered in the car's frontal section and there were attempts to correct this in time for the ill-fated third race, at the San Marino Grand Prix.