Reliability was an issue for Lewis Hamilton last season. Has that gremlin been firmly dealt with?

Image source, .

F1 journalist Dan Knutson in Barcelona: The first four races of the season are all “flyaways” in Australia, China, Bahrain and Russia. The next time the teams will have their transporters [and the engineers’ rooms on top of them] in the paddock will be when the F1 circus returns to Barcelona for the Spanish Grand Prix in mid-May.

The session is back under way. 

Thirty seven laps on the board for Fernando Alonso. How close to a Spanish GP race distance can he get before the chequered flag?

Steven Todd: John Surtees RIP - the word LEGEND is tossed about too readily nowadays, wholly appropriate in his case  

Lord Roger: John Surtees will remain a legend. I doubt that anyone will match his feat of titles on 2&4 wheels.

Q: R.I.P John Surtees. A legend and a gentleman.

We're still waiting for Carlos Sainz's Toro Rosso to be recovered so we can finish the day's testing. He had come to a stop on the main straight.

Forty minutes to go.

Just before the red flag Lewis Hamilton, who has had a quiet afternoon, posted his best time of the day with a 1:19.850 on ultra-softs to move up to fifth.

Red flagpublished at 16:09 Greenwich Mean Time 10 March 2017

16:09 GMT 10 March 2017

Red flag again. It's the Toro Rosso this time.

Bob Price: One wonders if the legend of John Surtees will ever be equalled in this modern era. An icon of motorsport

John Shockley: Privileged to meet John Surtees more than once at Goodwood FOS. An absolute gentleman and utter legend. Will be sorely missed.  

Even better now from Fernando Alonso as he does a 1:21.811 on softs. It's looking like an encouraging end to the day for McLaren. Still not great, but better than things looked this morning.

Fernando Alonso is up to 34 laps for the day, the latest of which is a 1:22.412. That's a personal best for the day but he remains P12.

There's one hour of testing remaining and I'll continue to provide updates on the closing stages but please send through your tributes to John Surtees. 

As Andrew Benson puts it, a legend.

Andrew Benson
Chief F1 writer

John Surtees is the only man to have won the grand prix world championship on both two wheels and four. A legend  

A statement on the Henry Surtees Foundation Facebook page reads:, external "It is with great sadness that we announce the death of our husband and father, John Surtees CBE.

John, ‪83, was admitted to St Georges Hospital, London in February with an existing respiratory condition and after a short period in intensive care he passed away peacefully this afternoon. His wife, Jane and daughters, Leonora and Edwina were by his side.

John was a loving husband, father, brother and friend. He was also one of the true greats of motorsport and continued to work tirelessly up until recently with The Henry Surtees Foundation and Buckmore Park Kart Circuit.

We deeply mourn the loss of such an incredible, kind and loving man as well as celebrate his amazing life. He has set a very real example of someone who kept pushing himself at his peak and one who continued fighting until the very end.

We would like to thank all the staff at St George’s Hospital and The East Surrey Hospital for their professionalism and support during this difficult time for us. Thank you also to all of those who have sent their kind messages in recent weeks.

Some very sad news. John Surtees, the 1964 Formula 1 world champion, has died.

Lewis Hamilton has been back out after the resumption of the session. Just the one lap before heading back in.

Thanks to you all for your many pictures from around the circuit today. Great to have extra eyes out there.

In fact, if anyone sees circuit cat can you get a picture? I am starting to worry I imagined it.