Chris Akrill:, external McLaren in for a testing season, playing catch-up to the likes of Ferrari. If they spring a surprise will run barefoot to Marenello!

Image source, Williams

Williams:, external Valtteri is wheeled back into the garage after his latest run. It's windy out on track which will mix things up a bit.

Andrew Benson
Chief F1 writer

"There is an update from McLaren. They say they will be out on track in 40 minutes and will come back to us with more details on the reason for the delay."

Silence on the circuit, with everyone back in the pits. One hour and 30 minutes of testing gone and still no McLaren.

Andrew Benson
Chief F1 writer

"Sauber caught the eye at the first test in Jerez with a fastest time of all on one day, and second fastest on the other three. But Marcus Ericsson, one half of an all-new driver line-up for the Swiss team this year, admitted on Saturday that this was solely down to the team running the car in a different spec from the others. 'We are not fooling ourselves and thinking we will fight for P1,' the Swede said. 'We are aiming to fight for points. We are happy with the pre-season so far and hopefully we can continue that trend.'

"Sauber had the worst season in their history last year, failing even to score a point. Ericsson said the team had made 'for sure a step, on the car and the power unit, although how big is difficult say. It's promising but we have to wait and see.'"

Sauber's Felipe Nasr managed just three laps this morning and he is currently back in the team garage.

They confirm they are having "general issues with the C34", adding that they are investigating the problem and aim to be back on the circuit as soon as possible.

Nico Rosberg is clearly unperturbed by his early venture off the circuit, he has passed the 20-lap mark, meaning he has more mileage under his belt than any other driver so far today.

Feeling Ire:, external Can you imagine if this year's McLaren turns out to be like the MP4-18 of 2003 and never races! I wonder what Alonso's thinking.....

As is often the case, the moment I rattle off an update on times someone only goes and sets a new fastest lap.

Carlos Sainz, on softs, clocks 1:27.991 to take Toro Rosso to the top of the timesheet.

1. Valtteri Bottas (Williams) 1:28.449 (9 laps)

2. Sebastian Vettel (Ferrari) 1:28.970 (15 laps)

3. Nico Hulkenberg (Force India) 1:30.221 (11 laps)

4. Nico Rosberg (Mercedes) 1:32.618 (20 laps)

5. Carlos Sainz (Toro Rosso) 1:37.232 (11 laps)

6. Romain Grosjean (Lotus) 2:12.700 (7 laps)

7. Daniil Kvyat (Red Bull) (11 laps)

8. Felipe Nasr (Sauber) (3 laps)

9. Fernando Alonso (McLaren) (no laps)

An improvement from Nico Hulkenberg as he completes a lap of the circuit in 1:30.221. He has the third fastest time of the day, behind Sebastian Vettel and pacesetter Valtteri Bottas.

Gary Brown:, external Never underestimate HONDA the car is yet to run at full power and the chassis seems good might be a surprise in Melbourne.

Image source, Force India

Force India:, external Car 27 leaves the pits as we return to track. Nico out to set his first times laps of the day.

Nico Hulkenberg joins Romain Grosjean, Carlos Sainz, Nico Rosberg, Sebastian Vettel and Valtteri Bottas in getting a time on the board, a 1:31.251.

Andrew Benson
Chief F1 writer

"I don't want to be a doom monger or anything, but it's now an hour into the final day of this test and the McLaren-Honda has still not gone out. Honda said earlier that it was 'time to give the power unit a final run with more testing. Stability is the main focus.' In which case, you have to ask, what's keeping them, if it's not yet another problem?"

Speaking of McLaren, there's still no sign of them on the circuit with one hour of testing gone...

Andrew Benson
Chief F1 writer

"Unlike McLaren, this has been a good test for Lotus, of whom Pastor Maldonado has topped the times on two of the three days so far. The team had a terrible season in 2014, with an unpredictable car lacking downforce and down on power because of the Renault engine. Having switched to Mercedes, and with a completely new car, Maldonado says he is encouraged. 'The car seems to be very consistent,' the Venezuelan said. 'I don't know if it is fast. There is a lot to do. We are not at the top of the potential of the car but it is quite positive."

Valtteri Bottas storms to the top of the embryonic timesheet with his first flyer, going round in 1:28.868.

Pastor Maldonado has the benchmark time, setting 1:24.348 in the Lotus on Saturday.

Nico Rosberg's Mercedes has had the last remnants of gravel hoovered out of it and is back on the circuit. He clocks 1:33.627 to go second.

Matthew Traynor:, external McLaren-Honda will surprise everyone with how competitive their car will be. Note, Red Bull did less miles last winter.