Valtteri Bottas topped the timesheets as the teams stopped for lunch on what is the final day of pre-season testing.

As ever, when the lights went green at 09:00, there was a queue of drivers eager to get to work, Felipe Nasr at the front.

Wasting no time at all, the Brazilian went on to post the first time of the day (1:46.530) as he was joined on track by Sergio Perez, getting his first taste of the VJM08.

As Rosberg inevitably took the top spot, on Pirelli development tyres no less, Perez posted 28.739 before improving to 28.682 on the mediums.

Fifty minutes into the session came the inevitable message from McLaren. "Bit of a delay with today's programme," said the Woking outfit, "the team are running some system checks, but hope to be out later this morning..."

As Ricciardo and Bottas finally got their names on the timesheets, leaving Verstappen, Maldonado and Button as the only drivers still to do so, out came the red flag when the Australian - not for the first time - stopped at the end of the pitlane. Shortly after, Red Bull revealed that the car was suffering an ERS problem which was being looked into.

Running the winter tyre, Bottas posted a 25.099 to go quickest, the Finn subsequently making further improvements on the soft (23.859) and then supersofts (23.63) to post the best time of the morning.

Nasr, also on the supersofts, took second with 24.023, while Perez slotted in behind with a 25.113.

Ten minutes before the break, Vettel bolted on a set of supersofts, and despite being quickest in S2 could only manage 23.469, 0.406s off Bottas' time.

On a busy morning which has seen the eight drivers complete 344 laps in total, minutes before the break Button headed out for an installation lap.

"We plan to be out again for the afternoon session," said the team, though it's hard to tell if their fingers crossed as they uttered the words.

And in case you're wondering, no we haven't forgotten Mercedes. To be in honest it's been a quiet morning for Nico Rosberg who with 69 laps under his belt has been the second busiest driver.

We have a distinct feeling that the German and his team are lulling us into a false sense of security before banging in a blinder this afternoon.

Morning Times - All Times Unofficial

Name	Team	Laps	Time	Gap
Bottas	Williams	46	1:23.063	125.365 mph
Vettel	Ferrari	52	1:23.469	0.406
Nasr	Sauber	73	1:24.023	0.960
Perez	Force India	54	1:25.113	2.050
Rosberg	Mercedes	69	1:25.186	2.123
Verstappen	Toro Rosso	49	1:26.267	3.204
Ricciardo	Red Bull	10	1:26.587	3.524
Maldonado	Lotus	35	1:28.272	5.209
Button	McLaren	2	No Time