Pierre Gasly is leading the times with a 1:18.647 in his Red Bull and he has just gone back on track for some more info-gathering. Hamilton, Hulkenberg and Russell are also keeping busy as well.

Chris Marsh: What's going on!? Has a Honda engine stopped working yet? It's not testing without a Honda failure.

There's still time, Chris.

Kayleigh- The Patron Saint of Grid Hunters: McLaren, Can you possibly go one day without doing something stupid? No more trips into the gravel please. Thank you, love you kind of. Kayleigh xoxo

It's a tough relationship.

Alexander Albon is on it straight away after the restart, moving up to fifth on the medium compound C3 tyres, sending in a lap of 1:19.967.

Bob McFeil: Please no. It can’t be. McLaren have broken down. My Tuesday, ruined.

Sorry, Bob. There's still time for them to turn it around.

We're back.

Racing Point aren't too fussed about the red flag. Refuelling time. Well, for the staff at least.

OK, thanks.

Well, Ferrari? What's going on?

Eoghan Brophy: Only six laps so far for Ferrari. Have they just decided they've done enough testing after last week or do they have some issues?

JOkora: What is @ScuderiaFerrari, external up to this morning? Probably installing new performance parts on the car. They should come out flying in the afternoon.

The recovery vehicle is out there trying to rescue the stricken Lando Norris so hopefully there isn't too much damage to his car and we can get going again soon.

Problem for Norrispublished at 10:24 GMT 26 February 2019

10:24 GMT 26 February 2019

Lando Norris has stopped in the gravel at Turn Three. We have a red flag.

A cracking day so for for Antonio Giovinazzi who is in second place. He's only had two races in his grand prix career and gets his big chance this season as Kimi Raikkonen's team-mate at Alfa Romeo.

1. Pierre Gasly (Red Bull, 1:18.647, 34 laps)
2. Antonio Giovinazzi (Alfa Romeo, 1:18.929, 32 laps)
3. Lance Stroll (Racing Point, 1:19.139, 26 laps)
4. Kevin Magnussen (Haas, 1:19.644, 32 laps)
5. Lewis Hamilton (Mercedes, 1:20.764, 40 laps)
6. Nico Hulkenberg (Renault, 1:20.781, 45 laps)
7. Charles Leclerc (Ferrari, 1:20.830, 6 laps)
8. George Russell (Williams, 1:21.102, 20 laps)
9. Alexander Albon (Toro Rosso, 1:22.001, 7 laps)
10. Lando Norris (McLaren, 1:22.306, 35 laps)

Chris Medland
F1 journalist in Barcelona

McLaren had an encouraging first week but then a scary moment during a filming day on Friday when a fire broke out in the team’s garage. Three team members were treated and quickly released from the circuit medical centre as fortunately it was not a more serious incident.

The car was checked for damage but nothing significant was found and it hasn’t disrupted their start to this test as Lando Norris has had a productive opening few hours today already.

Image source, Chris Medland

Stuart Oakley: It's with a heavy heart when I say, I fear we may not see Williams next season if, as expected, they have another disastrous year.

Stewart: Are Williams becoming The Simpsons of F1? As in, they've now been awful for as long as they were a genuinely top team? Or is that too harsh?

Too harsh on Williams...and The Simpsons I think there Stewart.

Image source, Simpsons

And just like that George Russell jumps up to eighth. A slight bit of better news for all you Williams fans out there.

Chris Medland
F1 journalist in Barcelona

Much like Mercedes earlier, Williams have been doing aerodynamic testing so far. It's easy to spot without even looking at the car, with the engine note staying constant and at lower revs along the pit straight as data is gathered at a set speed.

The team only managed 88 laps last week and both drivers admitted the car was compromised, but Williams insist it was nothing major that was missing, just a number of items rushed onto the car to get out on track.

Certain parts and small items didn't fit perfectly needed refining, but it's the sort of work all teams would do after day one - it just happened to be that day one for Williams was really day four for everyone else.

Image source, Chris Medland

Now, Patrick's explanation seems legit to me, but let's hear another verdict on Williams.