Detroit GP: Ayrton Senna, McLaren MP4-4 Honda, leads Thierry Boutsen, Benetton B188 Ford, and Pierluigi Martini, Minardi M188 Ford.
Ayrton Senna, McLaren MP4-4 Honda, leads Thierry Boutsen, Benetton B188 Ford, and Pierluigi Martini, Minardi M188 Ford.