Chris Medland
F1 journalist in Barcelona

It’s an overcast start to proceedings on the final day, but that’s actually a lot better than it could have been. The forecast earlier this week was for rain today, but it looks set to stay dry and give the teams another full day of running. They will want to get some wet weather data on the new tyres though, so Pirelli will artificially wet the track after lunch for a spell if required.

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Aero rakes o'clock this morning it seems.

There's a few cars looking like they've driven through a scrap yard and got some sort of metal grating stuck on them as a result as they measure air flow.

Image source, Getty Images

Andrew Benson
BBC Sport’s chief F1 writer

Haas will be running in an all-white livery for this final day of testing, removing both the decals of their Russian-based sponsor - a company owned by Dmitry Mazepin, a close associate of Vladimir Putin - and also the red, white and blue colours of the car that were designed to reflect the Russian flag, even if the team never admitted it. This, of course, in the wake of the invasion of Ukraine by Russia on Thursday, a decision by Putin that has created shockwaves around the world that have certainly reached the F1 paddock.

Many questions have been raised, about Haas, and about the country’s grand prix, scheduled to be held in Sochi in September this year.

For Haas, without the logos of their main sponsor, will the money Mazepin pays be forthcoming? Without it, are the team in any trouble? (Probably not - owner Gene Haas can afford to bankroll it if he wants; he just got to a point in 2020 when he decided he didn’t want to to the same extent any more.) But if the Mazepin money dries up, there is little point in the team holding on to their underwhelming driver, Mazepin’s son Nikita, whose place in the team secures it.

As for the race, can F1 race there now, a sport owned by a US company, with sanctions already imposed and more likely to come? Insiders are being coy about the outcome of a meeting held between F1 and the team bosses last night to discuss the issue. Sebastian Vettel has already made his position clear: “I should not go, I will not go. It is wrong to race in the country,” he said on Thursday. And Max Verstappen said: “When a country is at war, it is not right to race there.”

Now George Russell emerges, along with Pierre Gasly and Sebastian Vettel.

George Russell is back in the driver's seat this morning as the final day of testing get under way.

He's not gone out yet, possibly still polishing off his breakfast. Instead it is Red Bull to break the early silence.

Andrew Benson
BBC Sport’s chief F1 writer

Image source, Getty Images

Are Mercedes not having a great first test? After the end of the second day’s running, George Russell said that “some teams are looking pretty fast - a red team and an orange team in particular look very competitive”, confirming that the fact Ferrari and McLaren have been at the top of the times was reflective of strong performance from their cars, regardless of the usual caveats about testing.

Where are Mercedes, Russell was asked? “Certainly not ahead,” replied. "Pretty sure of that. They seem to have things well under control and they are on top of everything and they look very strong low fuel and high fuel and with the tyre management.”

Chief engineer Andrew Shovlin said that in their Thursday running, Lewis Hamilton had struggled with balance in the morning, but also had some reliability issues, and admitted that, while Russell “had a more productive session”, “we’ve still got plenty of issues to work on from a performance point of view”.

Now, the more regular followers of Formula 1 might roll their eyes at this point and say, “Pull the other one - we’ve seen this before." True - but that doesn’t mean that, last year, for example, Mercedes weren’t struggling in testing. They were. Or that Ferrari weren’t quickest pre-season in 2017 and 2018. They were. Both times, in the end, Mercedes turned things around.

Image source, F1.com

Here's how things finished up yesterday, where Ferrari's Charles Leclerc finished fastest.

Image source, Getty Images

Hello and good morning!

It's the final day of the first Formula 1 test before the new season. Let's see what it brings, shall we?