Bridgestone's hard tyre proved to be the fastest rubber in the heat of Istanbul for the first day of the Turkish Grand Prix at the purpose-built Istanbul Park race track. In warm, sunny and windy conditions, Heikki Kovalainen set the day's fastest time, a 1min 28.841secs, in his Vodafone McLaren Mercedes in the afternoon practice session.

Bridgestone's hard and soft compound presented competitors with a stern challenge to find a good set-up on the changing circuit surface. The morning practice session was temporarily stopped with a red flag period whilst some dislodged Astroturf was removed from the track. Nico Rosberg went fastest in this session, using the hard compound Bridgestone and his AT&T Williams to set a time of 1min 28.952secs.

What was significant about today's running?
Hirohide Hamashima - Bridgestone Director of Motorsport Tyre Development: "Today was mainly about track condition. Istanbul Park is a fabulous track, but it is not used very much during the year. This means it starts the weekend dirty and it takes time before rubber is laid on the surface to allow our tyres to work well. In the second session this improvement did not happen as much as we would expect and we are working to understand why this could be. Certainly, it was relatively windy today and this has an impact on the current generation F1 cars. Today we heard a lot of talk about lack of grip and graining, however that is usual for a Friday. Here we generally see one of the greatest track weekend evolutions of the season so tomorrow will be interesting."

How do you expect this allocation to work over the weekend?
HH: "This weekend looks to be a little difficult in terms of making predictions and the data from today shows there is still work to be done on set-up for teams, but also that the track is changing. Interestingly, we saw some big differences in car balance dependant on which compound was used, which is not something we have experienced to this extent so far this season. Track temperature is important here. If it gets hotter than today we expect the hard tyre to give more grip than the soft. If it gets cooler, we expect the soft tyre to offer better grip than the hard. Today was in the middle in terms of temperature, so grip levels and lap times were very similar between the compounds."

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