Fancy seeing a glimpse of Sebastian Vettel and Max Verstappen. Luckily, Greg Kingston is armed with a phone / camera and is not afraid to use it.

Thanks Greg.

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1. Sebastian Vettel (Ferrari) 1:20.168
2. Valtteri Bottas (Mercedes) 1:20.270
3. Stoffel Vandoorne (McLaren) 1:20.325
4. Max Verstappen (Red Bull) 1:21.014
5. Carlos Sainz (Renault) 1:21.212
6. Pierre Gasly (Toro Rosso) 1:21.318
7. Sergey Sirotkin (Williams, pictured) 1:21.822
8. Esteban Ocon (Force India) 1:22.231
9. Kevin Magnussen (Haas) 1:22.850
10. Charles Leclerc (Sauber) 1:23.914

We are still expecting to see Nico Hulkenberg (Renault) and Robert Kubica (Williams), but Mercedes have said there will be no Lewis Hamilton today.

Image source, Getty Images

Pierre Gasly has done 59 laps and is now in the garage. He's apparently off for lunch. It's alright for some.

BBC Sport app users may need to click on the link to see the tweet.

Michael Heal‏: Feel they should move testing for warmer temperatures. Honestly don't see the mileage in running two degree temperatures. Could they not just fly to Melbourne earlier for example? Another way would be for the authorities to fund the midfield teams to get to Bahrain.

Jon Bennett‏: Spicing up testing - I think it's more about the fan experience. The teams have a serious job to do, but testing is an ideal launch pad for fans who maybe haven't seen F1 before. Make it more accessible - maybe include a 'roadshow' to go with it.

Yash Fdo: Been a McLaren fan forever. would love to see them put a quick lap on the same tyre as the others to give us fans some indication. the wait still continues...

We said Max Verstappen and Sebastian Vettel could challenge leader Valtteri Bottas, and the Ferrari man has just moved fastest with an effort of 1:20.168.

Verstappen is also getting faster but still down in fourth.

Vettel's effort is 0.011 seconds faster than Daniel Ricciardo's best time of Monday.

Image source, Getty Images

We saw a picture of Charles Leclerc's Sauber being recovered. But what happened to him?

Luckily, the Sauber Twitter account can tell us.

"A tiny detour," is the way they describe spinning into the gravel. He has done 52 laps, but is now slowest. Kevin Magnussen, who also had a gravel holiday earlier on, is back out there and just moved faster than Leclerc.

Worryingly for Sauber, Leclerc is now a second slower than anyone else. Maybe there won't be a title push for Sauber just yet.

BBC Sport app users may need to click on the link to see the tweet.

Well, he was sixth. now Max Verstappen is fourth. Sebastian Vettel is also on the track so we could see Valtteri Bottas's time of 1:20.270 come under threat.

Image source, Getty Images

Max Verstappen, hampered by a fuel leak earlier on today, is now up to sixth. The five in front of him are Valtteri Bottas, Stoffel Vandoorne, Sebastian Vettel, Pierre Gasly and Carlos Sainz.

Andrew Benson
BBC Sport’s chief F1 writer

On Monday, Red Bull team boss Christian Horner was expressing his “concern” about Renault’s plans to focus on reliability over performance at the start of the season, before bringing more performance later on.

But Renault Sport boss Cyril Abiteboul says that it’s not quite as simple as that. “Reliability and performance and competitiveness go hand in hand,” the Frenchman said. “Last year we had to reduce the performance potential of the engine because of reliability.

"So the target is we need to start the season reliably so we can use the engine to its full potential, which we were not able to last year. So from a performance perspective the engine should be performing better. When they are reliable, components open up more options in terms of performance. When you work on reliability, you work on performance also.”

Abiteboul said the engine would start the season at a performance level “comparable to the end of last year when we were using the engine at its maximum potential, which has not happened on many occasions".

Image source, Getty Images

Scott Coe: How to improve testing? Televise it. Simple! Also, test at other tracks, not just Barcelona. Maybe spice things up by visiting tracks not on the calendar.

Adam Johnson‏: Why not have sprinklers around the test track that come on at random intervals, should keep the drivers on their toes :P

Benjamin Collins: Isn’t it obvious? Testing should be done on ice. Red Bull managed it for an advertising stunt a few years back and it would probably be about as inconclusive as regular testing!

Charles Leclerc had the track to himself. All he can do though is find the gravel after spinning.

That may be the last we see of him today.

BBC Sport app users may need to click on the link to see the tweet.

Just as I was saying we would see Lewis Hamilton. I wasn't lying, honest.

That was the original plan, but Mercedes have just tweeted saying that the plan has changed to "maximise our mileage after the poor track conditions limited running this morning".

So there will be more from Valtteri Bottas but we will have to wait to see the world champion again.

Charles Leclerc has done 51 laps, Sergey Sirotkin has completed 52. Valtteri Bottas, our leader, has done 54, more than anyone else.

We will see Lewis Hamilton, Robert Kubica and Nico Hulkenberg later on, a fuel leak has meant a frustrating day so far for Max Verstappen and Kevin Magnussen ran into the gravel so has also not been seen much.

Image source, Getty Images

Kobus Nell‏: You spice up F1 testing by bringing it to Kyalami! We would love it. Wouldn't it be nice to have non-championship testing venues? You can include places like Donington, Nurburgring, Zandvoort to cater to the purists.

Old Nick: So McLaren are running on ultra soft tires while everyone else is on Medium. Hmmm, is there not as much speed in that chassis as they claim?

Martin: How about a one-lap "qualifying" shootout at the end of the day, stream it using on-board cameras so no need for camera operators. I'm not sure it should be for championship points, but for fun / pride / pit lane garage position for Melbourne?

Image source, Getty Images

Time to see a bit more action, this time courtesy of the Formula 1 Twitter account, which shows Sauber's 20-year-old Charles Leclerc in action.

He is approaching 50 laps today, but is more than three and a half seconds off Valtteri Bottas' fastest time and a second and a half off Esteban Ocon in seventh.

Can the youngster, who won the Formula 2 title last year to earn his promotion, make Sauber competitive this year?

The team only picked up five championship points last season, all earned by Pascal Wehrlein, but it was not enough for him to stay in Formula 1 as he was dropped for Leclerc.

We haven't mentioned Max Verstappen much today and that is because he has only completed 10 laps, with his best time of 1:26.034 being the ninth fastest out of the 10 men that have set a time (Kevin Magnussen, who has only done six laps, is slowest).

Well, Red Bull have tweeted to say that Verstappen has been hampered by a minor fuel leak today.

BBC Sport app users may need to click on the link to see the tweet.

We had some videos earlier on from Greg Kingston at the track, now he has been out and about for a glimpse behind the scenes.

BBC Sport app users may need to click on the link to see the tweets.

Stewart: They should televise the testing to get more fans excited about the upcoming season. Look at how popular Alonso's Indy 500 testing session was on Youtube - people will watch testing. It doesn't need the full FOM treatment either.

Lachlan Gibbs‏: How to make the fans love Liberty Media, Step 1: Televise the Testing.

Yes, as someone who has been staring at the Formula 1 timing screen on my I Pad for the past five hours I definitely agree with this.

A good day so for McLaren with Stoffel Vandoorne second, setting his best lap on the purple ultrasofts.

Valtteri Bottas is out in front and is putting in a shift today. He has just done his 50th lap, the only driver to have reached their half century.

Elsewhere, Sergey Sirotkin has done 46, Charles Leclerc 44, Pierre Gasly 43 and Vandoorne and Sebastian Vettel have both done 35.

Andy K: Crazy idea but how about we just get done with testing and go straight into racing? Testing can be the Practice & Quali. We all know testing means nothing as teams hide away their strength.

Joseph Rogers: Off the back of the Winter Olympics, why not make F1 Testing an opening ceremony? Music, delegates, sponsors... Ross Brawn reading out the new rules, homage to the past etc. £10 tickets to draw new fans in, in the hope they get inspired to fork out for a GP.