Toyota's Timo Glock topped the timesheets at Bahrain today, the penultimate day of testing at the Sakhir circuit.

A stronger wind at meant that conditions were cooler than they have been in previous days but there was still a full day's running for the three teams in action.

Glock took over from Jarno Trulli, continuing the programme of set-ups. The German maintained the team's solid run, putting in well over 100 laps.

"That was another good day for us," said Glock. "We didn't have any major problems and we again made it through a lot of work. We concentrated on set-up and went through our programme smoothly. It has been a bit tricky to drive today because there was a lot of wind, which was also blowing from a different direction to yesterday when Jarno was driving. But in the end I'm happy that we did so much work and it's positive that we found some useful directions to work with."

"Again, we are delighted with how this test is going," added Pascal Vasselon. "Today was another very long day of testing. We are starting to run out of hours of sleep- so the car seems to be lasting better than our bodies! Today Timo completed another full set of runs. We worked on all parts of the car, including set-up, suspension, aero and tyres. The car is quick and consistent so this was another interesting day."

Following yesterday's problems with its KERS system, it was another difficult day for Ferrari, this time as a result of a gearbox gremlin.

Felipe Massa was back behind the wheel of the F60 today, and immediately got to work on different set up options. However, after just four laps he was forced to return to the pits because of a problem with his gearbox, a fault that cost the Brazilian two hours of track time.

Back on track, the 2008 World Championship runner-up began an endurance test, four runs of 15 laps with pit stops for refuelling. At the end of the day the Brazilian went back out to verify the car's set up, but due to an electronic problem on the first lap he had to stop and the F60 was brought back to the pits on the back of the breakdown lorry. As happened on Tuesday, safety procedures were in effect and those mechanics closest to the car wore protective suits to prevent possible electric shocks.

"We're coming close to the end of this long test session here in Bahrain and the days are more and more intense," said Aldo Costa. "We have to exploit what the rules permit in terms of tests, as far as reliability, development and research in terms of performance are concerned. There might be some problems ahead, like the ones we've had over the two days with the completely new components of the KERS or with experiments, like the ones we had on the gearbox this morning.

"As far as the KERS is concerned I have to say that we're quite satisfied with what we've seen so far," he added, "although there's still lots of work to do. We used a standard configuration for the aerodynamics here in Bahrain, with just some minor updates: the complete one we'll see at the next tests in Jerez and Barcelona, where we will conclude our preparation for the Australian GP."

For BMW, Nick Heidfeld tried different set-up solutions, carried out a couple of practice starts and evaluated tyre options. Whereas in the morning everything went according to plan, in the afternoon the car stopped twice on the track due to mechanical problems.

"Obviously that cost us some track time," admitted the German. "But despite this I managed to run for 444 kilometres and we made good progress with the development of the car. We are still learning the car and have already identified a few areas where we can make improvements."