Toby Godfrey: EXCITED !!! (Better?)

That's more like it! Capital letters makes everything more exciting.

The first day of the first test is UNDER WAY!

For real this time.

Image source, .

The above is a picture of Red Bull's 2018 car that they revealed at their launch.

The blue livery was solely their launch livery and the real thing has now been revealed below.

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Andrew Benson
BBC Sport’s chief F1 writer

Don’t expect things to really get going that quickly on this first day of testing. Nearly all the teams have done what are known as “filming days” - basically tests limited to 100km - in the last week.

But this first day of official testing will, initially at least, be about proving the reliability of cars before set-up work is embarked upon later this week, and true performance work in the second test next week.

Mercedes, typically, has bucked this trend, in the last couple of years managing more than 100laps even on the first day of testing. No one would be surprised if the world champions did the same again this year.

Toby Godfrey: Excited

You sound it, Toby.

Well the delay does at least give me the chance to ask you all to get involved in the chat, otherwise it will largely just be my ramblings for the next 10 hours and no-one wants that.

All the cars for 2018 have been revealed and I will be popping each one in this page over the course of the morning, but which one do you like the look of best and why?

Also, tell us in one word the very first thought you had the moment your team's car was revealed. I.e McLaren - orange etc.

Get involved via #bbcf1 or text in on 81111 (UK only)

Oh, no it's not. It's been delayed by 10 minutes.

Well that's made my use of capitals below to emphasise my excitement look a little foolish.

The first day of the first test is UNDER WAY!

Andrew Benson
BBC Sport’s chief F1 writer

Image source, Getty Images

Renault have warned not to expect too much in the way of lap times from their teams in this first test.

Renault Sport managing director Cyril Abiteboul told Autosport that the company have made “some compromises for engine number one in order to make sure that we have got the right platform”. In other words, they have backed off on the risks they have taken on performance when it comes to parts used in the first few races. And he says that in this first test “everything will be massively tuned down for obvious reasons”.

Abiteboiul said the “target” was to start the season with “more or less the same performance level as we finished (last year) in Abu Dhabi”. More performance will come with updated parts as the European season gets going.

Remember that all engine companies will be facing the same battle of performance against reliability as a result of the restriction of engines to three this year, from four in 2017.

It is warmer in Spain than it is in most of the UK, but only just. A touch over 4C.

Testing gets under way in just FIVE minutes.

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Mercedes: Bottas/Hamilton

Ferrari: Raikkonen

Red Bull: Ricciardo

Force India: Mazepin

Williams: Stroll/Sirotkin

Renault: Hulkenberg/Sainz

Toro Rosso: Hartley

Haas: Grosjean

McLaren: Alonso

Sauber: Ericsson

Andrew Benson
BBC Sport’s chief F1 writer

Force India and Toro Rosso became the final two teams to unveil their 2018 cars before the start of pre-season testing on Monday.

The Force India appears very much an evolution of last year’s car, which finished fourth in the constructors’ championship.

Force India have set themselves the target of maintaining their fourth-place finish this season, despite what is expected to be a greater threat from McLaren and the factory Renault team.

Image source, .

Toro Rosso are embarking on their first season with new engine partner Honda.

The Japanese manufacturer split from factory partner McLaren last year just three years into an arrangement that was expected to last nearly a decade after continuous poor performance and reliability. Red Bull has taken on Honda with its junior team to give it options with the senior team in the future.

This is effectively a proving year for Red Bull to decide whether to switch from Renault engines for 2019, following years of coolness in their relationship as a result of the French company’s inability to match standard-setters Mercedes one engine performance.

Image source, Getty Images

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We've got four days of testing fun ahead of us with the first test getting under way in just under 20 minutes.

No lie-ins for the journalists this morning, however, as Force India and Toro Rosso became the final two teams to launch their 2018 cars at the circuit.

Andrew Benson
BBC Sport’s chief F1 writer

Image source, Getty Images

Last week - car-launch week - was all about optimism and hope of improvements from 2017. This week - the first four days of pre-season testing - is where that optimism collides with reality.

By and large, the public utterances will remain positive, but by the end of the next fortnight every team up and down the pit lane will have a pretty good idea what sort of season awaits them. As such, the pit lane at the Barcelona track this morning is full of engineers and senior figures awaiting with nervous anticipation the events of the next eight days of running, from today until Thursday, and next week from Tuesday to Friday.

Everyone has a lot of work to do to understand their new cars in the limited time before they are shipped to Australia. The secrets will be revealed slowly, so please stick with us this week and next as Formula 1 2018 begins to take shape.

It's Monday.

It's the start of the week, the weekend seems like a million miles away and it's most probably blooming freezing outside.

BUT this isn't just any normal Monday because today is the first day of pre-season testing. It's basically the start of the 2018 Formula 1 season.

Monday? More like MonYAY.