Canada for illegal brake ducts, even though, in Williams's case, this proved to be a manufacturing error and had not given them any aerodynamic or cooling gain. Friday drivers The bottom 6 teams in the 2003 Constructors' Championship were entitled to run a third car in free practice on Friday. These drivers drove on Friday but did not compete in qualifying or the race. Practice and qualifying Four practice sessions were held before qualifying - two 60-minute sessions on Friday and two 45-minute sessions on Saturday. All of the teams, with the exception of Ferrari, Williams, McLaren, and Renault, were permitted to run three drivers on Friday. Rubens Barrichello topped the timesheets in practices one, two, and three, with times of 1:11.354, 1:10.365, and 1:10.911 respectively. Jenson Button, driving for BAR, however, prevented Barrichello from a clean sweep in the second Saturday session: his time of 1:10.056 was 0.143 quicker than second-placed Michael Schumacher. Third was Takuma Sato, Button's teammate, whilst Barrichello languished in fourth. However, despite the pace of the Ferraris, their Bridgestone tires had grained in the long runs, meaning that balls of rubber would form on the surface of the tire, reducing mechanical grip. Qualifying was split into two sections. In the first session, dubbed "pre-qualifying", each driver took turns to record one lap at a time. The order the cars ran in was the reverse order to the classified results at the 2004 Canadian Grand Prix. For example, Michael Schumacher won the race, so would be the last car to run in pre-qualifying. The second qualifying session (dubbed "qualifying") repeated this process (with the drivers running in reverse order to the pre-qualifying results), but with the caveat that the drivers would not be allowed to alter their fuel loads between then and the race. The fastest time in the second session would take pole. As in 2003, setups and fuel loads could not be altered between the end of the second qualifying session and the race. Rubens Barrichello started from pole from teammate Michael Schumacher after setting a time of 1:10:223. Michael Schumacher started second, making it an all-Ferrari front row. BAR locked out the second row, with Takuma Sato lining up ahead of team leader Jenson Button. Williams locked out row three, with Juan Pablo Montoya in fifth, ahead of Ralf Schumacher. A gearbox issue prevented Jarno Trulli in the Renault from setting a lap,