After a bit of a lull we've just had a flurry of activity. Let's bring you up to speed: 

- Valtteri Bottas goes fastest for Mercedes with a 1:21.099 

- Fernando Alonso sets the first timed lap of the day for McLaren, despite Honda's claims to the contrary - a 1:23.956 on the soft. He's in fourth at the moment. 

- Lance Stroll's Williams also sets a time, a 1:27.848 on the soft rubber, followed a short time later by a 1:23.750 - good for third place. 

- Jolyon Palmer, having gone off earlier in the Renault, has put in a few laps on the medium tyre and is now sixth with a best time of 1:25.561.

Andrew Benson
Chief F1 writer

Image source, AP

These Ferrari lap times continue to be impressive. 

Sebastian Vettel is a few hundredths quicker than Valtteri Bottas so far this morning, despite using the medium tyre and the Mercedes the soft. 

Pirelli has not given an off-set between the various tyre compounds yet, saying it is too early to be sure. But it is aiming for a second between each. And the teams are so far saying that it does indeed look like there is a second between the soft and super-soft, but well over that - perhaps as much as two seconds - between the soft and medium, at least at Barcelona and in these conditions. 

Of course we don't know fuel loads, engine modes etc etc. But the Ferrari at least appears to be in the ballpark.

Don't forget we want your observations on pre-season testing too. 

Get in touch using #bbcf1 and we'll share as many as we can.

The Ferrari of Vettel is the only car out there right now. He moved top of the timing screens a few minutes ago with a 1:21.609 on the medium tyre.  

Andrew Benson
Chief F1 writer

Image source, @pirellisport

One of the biggest unknowns going into pre-season testing was how the tyres would work. Pirelli has been set the task this year of producing tyres on which drivers can push hard without running into thermal degradation. There was scepticism among drivers and teams, but so far it seems that is exactly what has happened.

Drivers are reporting very low degradation, which means they can push hard for many laps at a time. Not only that, but if the tyres do get overworked - for example in the final sector - they can be brought back.

This is a huge relief for purists who had tired of watching races in which drivers cruised around seconds off the pace to eke out the optimum stint lengths from tyres that turned to liquorice if they were driven hard for more than a lap at a time.

The flip side is that, right now, the tyres appear to be too hard and are going on too long. Pirelli racing director Mario Isola said: “In general, the feeling is the range is a bit too hard,” although he did point out that: “It is cold and the cars are not at their top performance.”

Team engineers were a bit more vocal, one saying the tyres were “made of stone”, and adding that this was why the cars were not as much faster than 2016 cars as expected. But if people are concerned about one-stop races, it should be easy enough to avoid them, simply by erring on the side softness when it comes to tyre choices.

Lance Stroll is heading out in the repaired Williams, which need fresh parts shipping in overnight after the rookie's turn-nine indiscretion yesterday.

Keep it on the island, Lance. 

Valtteri Bottas has been doing a lot of the donkey work for Mercedes so far at this test but he's cutting loose a bit this morning, with a 1:21.632 on the soft tyre. I'm willing to be corrected, but I'm pretty sure that's his personal-best time this week,

McLaren, after the problems of the past two days, are quietly getting on with it today. No time on the board but eight laps ticked off without obvious drama.

1 Vettel, Ferrari - 1:22.222 (12 laps) Medium 

2 Bottas, Mercedes - 1:22.816 (15) Supersoft 

3 Kvyat, Toro Rosso - 1:25.423 (12) Medium 

4 Ricciardo, Red Bull - 1:31.492 (5) Soft 

5 Celis Jr, Force India - 1:44.478 (6) Supersoft

6 Stroll, Williams (0) 

7 Alonso, McLaren (8)

8 Grosjean, Haas (4)

9 Palmer, Renault (4)

10 Ericsson, Sauber (6)  

I'm pretty sure my parents had this picture on their lounge wall in the 1990s.

Valtteri Bottas pulls out the Mercedes garage in the W08.

Not sure who that chancer on the left is.

Image source, Getty Images

Dan Knutson
F1 journalist in Barcelona

It's handy that Jolyon Palmer spun at turn three, as after yesterday’s session he was asked about that very bend. 

“I haven't done it flat yet but it's there or thereabouts,” he said. “It feels really quick. That's the biggest difference, the high-speed performance. Turn three, Turn nine, both really quick. It will be flat I think, very soon.” 

It is doubtful that he would have taken Turn three flat this early in the morning with a cold track and cold tyres.

Dan Knutson
F1 journalist in Barcelona

Image source, Getty Images

Daniel Ricciardo is back in the Red Bull today. 

Yesterday Max Verstappen was third quickest but over a second off the pace of Mercedes and Ferrari.

“For sure they will always be quick,” he said of Red Bull’s main rivals, “but for us at the moment it is all about just getting the mileage in, and see if there are some issues. But we had a very positive day and we will focus later on on lap times.

“I think it is too early to really compare. They did their own programme, we do our programme, and we will see later in the test how good they are.”

The marshals have cleared the stricken Renault and we're green again.

I'm bunging a tenner on 'Hattie Jacques'.