The race is one of the most controversial in F1 history, as the culmination of Alain Prost and Ayrton Senna's tumultuous two-year rivalry as teammates at McLaren.

The Japanese Grand Prix decided the 1989 Drivers' Championship in Prost's favour, after a collision on lap 47 at the final chicane between him and Senna put them both off the track.

While Prost abandoned his stalled car, Senna restarted his, made a pit stop to change his front wing, and overhauled Alessandro Nannini to take victory.

Nicola Larini was fastest in the Friday morning pre-qualifying session for the second Grand Prix in a row, the Osella driver just edging out Philippe Alliot in his Larrousse-Lola.

The Onyx team failed to get either car through to the main qualifying sessions for the first time since the third round at Monaco, as Stefan Johansson could only manage seventh after a fuel pump failure.

The Williams of Riccardo Patrese was half a second behind Mansell in fifth place, and joining him on row three was fellow Italian Alessandro Nannini in his Benetton-Ford using the development HBA4 V8 engine.

To improve his straight-line speed, Prost had his Gurney flap removed before the race, without Senna's knowledge, as revealed by Formula One journalist Maurice Hamilton.

This put Senna's car directly in the aerodynamic tow from the leading McLaren, negating much of Prost's straight line advantage.

Through the infamous 130R, ultra high-speed, left curve, Senna cut Prost's lead still further, putting his MP4/5 only two car lengths behind his rival.

With their wheels locked and their engines stalled, the two cars slid to a halt in the mouth of the partially blocked chicane escape road.

While Prost unbuckled his belts and left his car (thinking this race was over and the World Championship finally settled in his favour), Senna gestured to the marshals to push his down the escape road.

Nannini finished in second place, followed by the two Williams-Renaults of Riccardo Patrese and Thierry Boutsen who had driven in tandem and off the pace throughout the race.

Behind Piquet were two British drivers who also benefited from the misfortune of others, and while Martin Brundle's sixth-place finish was remarkable enough, Derek Warwick had come from the back row of the grid in his Arrows to take a seventh place.

In a ploy that worked a treat for him, before the race Warwick had taken the extraordinary step of removing virtually all downforce from his car in the hopes that the extra straight line speed would give him an advantage.

Senna personally alleged that the decision had been made by FISA President Jean-Marie Balestre to give the championship to his fellow countryman Prost (the race stewards and Balestre both denied this was the case, stating that the FISA boss wasn't even present at the stewards meeting when the decision to disqualify Senna was made).

This would prove to be Alessandro Nannini's only victory in a Formula One career that was cut short by a helicopter crash almost exactly a year later, which severed his right forearm.