Andrew Benson
Chief F1 writer

"Oops. Not a good start to the day for Sebastian Vettel, who has taken over the Ferrari from Kimi Raikkonen for the final two days of the test. The four-time champion has gone off into the gravel on his out lap. The cause of the incident is unclear for now, but it appears as if the German may have lost the car approaching Turn Five and simply spun."

...and is in the gravel at Turn 5. Looks like he spun off. He is out of his car and out comes the red flag.

The circuit is open and no messing about from Sebastian Vettel, he is straight out for Ferrari...

F1 journalist Dan Knutson: "After two sunny days, a front has moved in on the Circuit De Barcelona-Catalunya and rain is forecast for later in the day. The air temperature is 6.8C and the track temperature is 9.4C as the green light at the end of the pit lane signals the start of the day."

Here is the driver line-up for today:

Mercedes: Lewis Hamilton

Red Bull: Daniil Kvyat

Williams: Felipe Massa/Valtteri Bottas

Ferrari: Sebastian Vettel

McLaren: Jenson Button

Force India: Pascal Wehrlein

Toro Rosso: Max Verstappen

Lotus: Pastor Maldonado

Sauber: Marcus Ericsson

Andrew Benson
Chief F1 writer

"Half-distance in the team's preparations for Formula 1 has passed, and there are only six days left before the cars finish pre-season testing and are packed up and then sent to Australia for the first race of the season.

"So far, testing has been intriguing. Ferrari appear to have made a genuine step forward, Williams and Red Bull will be in the mix, and McLaren-Honda look as if they might just finally be extricating themselves from the mire of unreliability that afflicted their first five days of 2015. But Mercedes, clearly and obviously, remain the team to beat.

"Will those impressions be changed over the forthcoming six days, starting this morning at the demanding Circuit De Barcelona-Catalunya?"

Image source, Getty Images

Twenty one days and 21 hours; 31,500 minutes; 1,890,000 seconds. Whichever way you look at it, the first race of the 2015 Formula 1 season is fast approaching.

Just over three weeks until lights out at the Australian GP, and we have just passed the halfway mark in pre-season testing.

Is the reigning champion looking in good shape? Who could be his biggest challengers? All that and more could become clearer this weekend...