Barrichello tops wet Sepang warm-up.

The first rain of the Malaysian Grand Prix weekend arrived overnight on Saturday, leaving the Sepang circuit soaking wet for the start of the pre-race warm-up session.

Rubens Barrichello led the way for Ferrari, underlining the performances he has shown in practice and qualifying by heading the field by over a second on a lap set right at the end of the 30 minute session.

The Brazilian's nearest challenger was McLaren's David Coulthard, showing an improvement over his qualifying form, although nothing was being read into the performance due to the conditions. With team-mate Mika Hakkinen languishing down in 13th position, it appears that the McLarens are still struggling to get on the pace.

A late spate of fastest laps saw Heinz-Harald Frentzen demoted from first to sixth at the flag, with Jordan team-mate Jarno Trulli leading the pursuit of Barrichello and Coulthard. Finnish sensation Kimi Raikkonen matched the Italian blow-for-blow to take fourth spot, narrowly ahead of wet-weather star Jos Verstappen in fifth. Michael Schumacher, the ultimate rain man, was only seventh.

The majority of the field opted to run intermediate tyres, despite the amount of water on the circuit. Without further precipitation during the session, all hoped that the continuing humidity and watery sunshine would dry the line sufficiently for their choice to be right, but some still had to make the switch to full wets before the mid-point.

Giancarlo Fisichella spun early on, joining Fernando Alonso and Eddie Irvine as opening minute casualties - although all were able to continue. Unluckiest man in the session was the Italian's team-mate Jenson Button, who was again restricted to just a handful of laps by problems on his Benetton, leaving him stranded at the foot of the charts, behind both Minardis.

Gaston Mazzacane showed well for Prost, taking 16th between the two Jaguars, while qualifying sensations Ralf Schumacher and Juan Montoya were only eleventh and twelfth respectively. Nick Heidfeld underlined Sauber's potential by taking eighth.

Race morning warm-up - Malaysian Grand Prix.

1. Rubens Barrichello Brazil Ferrari-Ferrari 1min 49.763secs
2. David Coulthard Britain McLaren-Mercedes 1min 50.846secs
3. Jarno Trulli Italy Jordan-Honda 1min 51.046secs
4. Kimi Raikkonen Finland Sauber-Petronas 1min 51.265secs
5. Jos Verstappen Holland Arrows-Asiatech 1min 51.508secs
6. Heinz-Harald Frentzen Germany Jordan-Honda 1min 52.061secs
7. Michael Schumacher Germany Ferrari-Ferrari 1min 52.316secs
8. Nick Heidfeld Germany Sauber-Petronas 1min 53.352secs
9. Olivier Panis France BAR-Honda 1min 53.470secs
10. Jacques Villeneuve Canada BAR-Honda 1min 53.482secs
11. Ralf Schumacher Germany Williams-BMW 1min 55.109secs
12. Juan Montoya Britain Williams-BMW 1min 55.278secs
13. Mika Hakkinen Finland McLaren-Mercedes 1min 57.064ecs
14. Jean Alesi France Prost-Acer 1min 57.832secs
15. Eddie Irvine Britain Jaguar-Cosworth 1min 58.322secs
16. Gaston Mazzacane Argentina Prost-Acer 1min 58.416secs
17. Giancarlo Fisichella Italy Benetton-Renault 1min 58.565secs
18. Luciano Burti Brazil Jaguar-Cosworth 2min 01.120secs
19. Enrique Bernoldi Brazil Arrows-Asiatech 2min 01.630secs
20. Fernando Alonso Spain Minardi-European 2min 01.771secs
21. Tarso Marques Brazil Minardi-European 2min 04.349secs
22. Jenson Button Britain Benetton-Renault 2min 07.047secs