An update from McLaren.....
So we may see Alonso again before the day is out.
@shailesh: He is. In fact, he's due to speak to the media later this afternoon.
Bottas has just completed his 50th lap now.
But Rosberg has just completed two race distances!
Ricciardo just set the fastest first sector but didn't back it up in sectors two and three. As expected, there is a lot of pace left in these cars.
@NanduSreevalsan: A race distance at Jerez is 67 laps and he's now done 136. A bit worrying for the rest of the teams on day one.
@aditya: Not very much! They do often follow the data and talk to the engineers, but they also talk to the media and complete other mundane tasks. Jenson Button was in the garage to watch Fernando Alonso complete his first lap this morning and we had a pleasant chat with Max Verstappen in the morning.
@Matt: It looks that way at the moment. But the other teams will start to show their true pace as pre-season testing continues in Barcelona.
We've got another lull in the track action at the moment. All seven of the cars we have here today are in the pits.
That tweet from McLaren was posted about an hour ago. Still no sound from the McLaren garage.
Ericsson has broken the silence as he heads out for his 44th lap of today.
@MichaelDuncan: I've no doubt Mercedes has a lot left to extract from the car. But just because a car does a short run does not mean it was pushing (or necessarily on low fuel). The main thing to take from today is that Mercedes was best prepared for this test and have a very reliable car straight away. Single lap times are not so important today for any of the teams.
@FerrariFan: I've just updated the times and lap counts at the top of the page. Vettel has 33 so far today and is in the garage.
@MichaelDuncan: You can't really compare long-run pace at this time because the other cars haven't done any long runs.
@Lachuchelsea: The session ends at 17:00 here in Spain. So that's in one hour and ten minutes.
Vettel just went for a brief one-lap run. He now returns to the pits and drives to the exit for a practice start.
And back out he goes. Carlos Sainz is also on track at the moment in the Toro Rosso.
Vettel crosses the line this time to start a lap. Let's see if he completes it this time.
Vettel sets a new fastest lap with a 1:22.690. That's 0.460 faster than the rest at this stage.
@vettel: Yes, Lotus is due to arrive later today, so they will be back in the paddock tomorrow.
And now we have a red flag. I'm assuming that's for Sainz as Vettel just zoomed past our media centre.
So that red flag comes out more or less exactly as we enter the final hour of the session.
@MichaelDuncan: As we've said, headline times aren't the be all and end all at this stage.