1986 proved to be a tough year for both Mansell and the Williams team, off the track at least. After a pre-season test session at the Paul Ricard Circuit in the south of France, team owner Frank Williams was involved in a horrific road accident which left him a tetraplegic. Williams would not return to the scene until making a surprise appearance at the British Grand Prix at Brands Hatch where Mansell and Piquet finished 1–2. Williams's absence from the day-to-day running of the team actually created tension between the team and engine supplier Honda. The Japanese giant regarded dual World Champion Nelson Piquet as the team's number one driver (they were reportedly paying the bulk of Piquet's multimillion-dollar retainer) and were reportedly unhappy that the team's co-owner and Technical Director Patrick Head did not rein in Mansell during races and allowed him to take both points and wins from Piquet. As it was, while Williams dominated the Constructors' Championship, the two drivers took enough points from each other to allow McLaren's Alain Prost to sneak through and win the Drivers' Championship.