The 1989 Italian Grand Prix was a Formula One motor race held at Monza on 10 September 1989. It was the twelfth race of the 1989 Formula One season. Alain Prost took his fourth win of the season after McLaren team-mate and pole-sitter Ayrton Senna suffered an engine failure with nine laps to go, thus extending the Frenchman's lead over the Brazilian in the Drivers' Championship to 20 points. Knowing that he was moving to Ferrari for 1990, Prost dropped his winners' trophy from the podium into the crowd, to the severe disapproval of his team manager Ron Dennis. Gerhard Berger, the man Prost would be replacing at Ferrari, recorded his first finish of the season with second, followed by the two Williams of Thierry Boutsen and Riccardo Patrese. The final points went to Jean Alesi in the Tyrrel