Jerez test - day two: 23 June.

As was the case on Wednesday, Juan Pablo Montoya topped the timesheets as testing at Jerez headed into the second day today [Thursday].

The McLaren driver ended the day with a best time of 1m 17.405s to come home ahead of the BAR duo of Jenson Button and Takuma Sato. Montoya's best time came despite being forced to bring his day to an early end after an engine problem in his MP4-20, with an engine change taking place overnight ahead of the third day of the test.

Montoya was due to spend the day working on suspension and gearbox development work but found himself also involved in performing the Michelin tyre development work which had been scheduled for team-mate Alex Wurz. However the Austrian driver only completed eights before his day came to an end when he suffered a trapped nerve and was forced to pull out of the rest of the day on medical advice. Pedro de la Rosa will take over from Wurz for the final day of the test on Friday while Kimi Raikkonen will also be on track in place of Montoya.

With Button and Sato second and third for BAR after taking over driving duties for the second day, Franck Montagny had to settle for fourth place in the leading Renault with Ricardo Zonta's Toyota sandwiched between Montagny and Heikki Kovalainen in the sister Renault.

The Anglo-French team experienced a frustrating day, with tis programme disrupted by a number of stoppages which cost both drivers valuable track time and prevented any cohesive work on anyhting but the latest tyre programmes for Michelin.

"We had another difficult day, but nevertheless completed some useful running - particularly with Franck's car towards the end of the day," test team chief engineer Christian Silk commented, "We are hoping for a trouble-free day tomorrow, when Fernando [Alonso] will once again be back in action, in order to complete the essential items of our preparation for the next two races."

Veteran Olivier Panis - who will drive the third Toyota at Magny-Cours - finished in seventh place with Christian Kliens Red Bull eighth and Antonio Pizzonia ninth as the Williams team took to the track for the first time since the announcement that engine supplier BMW is to take the Sauber team for the 2006 season.

Working on preparation for the upcoming French Grand Prix at Magny-Cours, Pizzonia set a quickest time of 1m 18.689s to finish ninth, while team-mate Nick Heidfeld finished with the 13th quickest time.

"Antonio spent today's session tyre testing with Michelin while Nick Heidfeld completed some exploratory running of the new MK2 bodywork," test team manager Tim Newton said. "Over the course of the day, we identified some expected teething problems which we will be working on this evening before re-evaluating tomorrow. At present, it looks promising but we have some homework to do. Both Nick and Antonio will be on duty again for the team tomorrow."

With Wurz tenth despite his problems, David Coulthard in the second Red Bull car had to settle for eleventh with Jacques Villeneuve twelfth, although his fastest lap of 1m 19.611s was a second off his best time from Wednesday.

"In the morning we evaluated new aerodynamic configurations and packages, and then continued with some set-up work," test engineer Paul Russell said. "Later we did long runs to further assess Michelin tyres for the race in Magny-Cours. We achieved what we planned for today and seem to have good results."

Felipe Massa will complete the test on Friday continuing to work on the Michelin tyre programme and also run a number of aerodynamic tests.

Meanwhile at Barcelona, Ferrari continued with its latest test with World Champion Michael Schumacher and Luca Badoer both taking to the track.

The two drivers worked mainly on Bridgestone tyre development, new mechanical components and aerodynamics, with Schumacher completing a total of 68 laps with a fastest time of 1m 16.045s and Badoer setting a best time of 1m 17.007s.

Testing continues at both circuits tomorrow, with Jordan set to give the EJ15B its first run-out at the hands of Narain Karthikeyan and Tiago Monteiro alongside Ferrari in Barcelona. The car was due to run today but a missing part has seen the debut put back a day.

Leading times (23 June) - Jerez:

1. Juan Pablo Montoya McLaren- Mercedes 1m 17.405s 56 laps
2. Jenson Button BAR-Honda 1m 17.580s 113 laps
3. Takuma Sato BAR-Honda 1m 17.764s 119 laps
4. Franck Montagny Renault-Renault 1m 17.824s 79 laps
5. Ricardo Zonta Toyota-Toyota 1m 17.962s 106 laps
6. Heikki Kovalainen Renault-Renault 1m 18.136s 67 laps
7. Olivier Panis Toyota-Toyota 1m 18.530s 40 laps
8. Christian Klien Red Bull-Cosworth 1m 18.823s 69 laps
9. Antonio Pizzonia Williams-BMW 1m 18.969s 62 laps
10. Alex Wurz McLaren-Mercedes 1m 19.237s 8 laps
11. David Coulthard Red Bull-Cosworth 1m 19.439s 62 laps
12. Jacques Villeneuve Sauber-Petronas 1m 19.611s 108 laps
13. Nick Heidfeld Williams BMW 1m 19.990s 28 laps

[all cars on Michelin tyres]

Track conditions: Sunny and hot.

All times unofficial - courtesy of Sauber.