Adrian Sutil posted the 12th fastest time in the practice session ahead of the Turkish GP but Force India is still worried.

With the track at the Istanbul Park Circuit seldom used for racing activities, both the drivers concentrated their running on the second session when more rubber had been laid down.

Sutil's 1:29.864 was still good enough for the 12th place on the morning time sheet, while Fisichella (1:30.729) was 18th.

In the afternoon, Sutil clocked 1:30.081 to finish 17th, just ahead of Fisichella (1:30.091).

"We had no problems on the car today and everything worked well, but the grip level was not good out on the circuit," Sutil said.

"It was a bit dusty, and the tyres were very difficult to come to terms with, it didn't seem like we had enough grip. We now have to see what we are going to do but it may be different when the circuit has a bit more rubber down," he added.

Fisichella too struggled with balance even though the Italian was not too unhappy. "The balance was not so good at the beginning of this morning's session as the car was a bit too pointy and nervous, but we went in the right direction and made some positive steps.

"On the long run on harder tyres we were quicker but unfortunately I couldn't time a better time on the softer tyres as I had the coming together with Nakajima through turn 12," he added.