Exhausted by the internal war at McLaren and the controversies that marred the grueling 1989 season, Prost left for Ferrari in 1990. There he showed all his class by surpassing his teammate Nigel Mansell and developing the Ferrari 640 to perfection, which allowed him to win 5 victories, including the magnificent one in Mexico, and therefore to be in the running for the title. At the end of the season, the Ferrari proved to be very efficient in racing conditions. Nevertheless, this first season in red was not without its hitches for the Frenchman with his direct character and sometimes scathing remarks: his relations with the Italian media, the Ferrari staff and Mansell became poisoned, with the high point being the start of the Portuguese GP, where Mansell cut Prost off and allowed the McLarens to pass!
For his part, Senna, the undisputed darling of the British team, arrived in Japan in a comfortable position: one more win (6) and a 9-point lead (78 to 69), the equivalent of a victory, over his opponent. Suffice to say that Prost had to win at Suzuka to still hope to play for the title, while, for his part, a withdrawal by the Frenchman chinese thailand data would guarantee Senna the title on the spot... However, despite this brilliant season, Senna had not digested Suzuka 1989 and especially its consequences. The media brawl with Balestre, the blacklisting by the sporting authorities and the humiliating apologies he had to make at the start of the season, under penalty of being stripped of his license, all this had cultivated in him an anger that was eating away at him from the inside. Convinced that he was the victim of history, that he was the object of a plot by the Franco-French Balestre-Prost axis (which goes back to Monaco 1984!) and wounded in his pride, Senna did not turn the page.