Back to the action and the Lotus and Williams return to the track now the Toro Rosso has been cleared.
@quadge: No confirmation of that yet
Another red flag. This time its the Williams that's stopped at Turn 4.
McLaren has now confirmed it will take no further part in today's test, bringing an early end to its second pre-season test. Just four days left of testing before Melbourne now.
@bongc888: We don't know at the moment, the team are investigating. It seems like an odd accident, but I'm not going to speculate without any hard facts.
More information coming through from Sainz's recent stoppage. It seems he was sent to the medical centre afterwards but is fine and is now back in the garage. We've sent Nate down to Toro Rosso to find out more.
It seems there was some front wing damage to the Toro Rosso, so most likely Sainz hit the barriers at Turn 4.
Grosjean has gone fastest with a 1:24.681 on the soft tyres
Felipe Nasr has also improved to a 1:24.956 in the Sauber but he's on super-softs
@dnero: We'll see what the cause of the accident was this afternoon once the team has finished its investigations, but even without that crash they are definitely behind. The car is clearly pretty quick, but the question is whether they can exploit its full potential and get it running reliably in the space of less than three weeks. Red Bull managed an impressive turnaround from testing to the first race last year, but each team is different.
Vettel, Nasr and Rosberg are the only cars on track right now.
Grosjean is a fan of the soft times right now. Back on track in the Lotus as he looks set to complete over 100 laps before the end of the day.
Actually it looks like Grosjean is now on the super-softs so we might see an even quicker lap...
And we do a 1:24.067 - the fastest of the test so far.
Bottas is back on track after that stoppage not so long ago. He's on the hard tyres and it looks like Williams has had no interest in chasing times so far today.
@bongc888: This is testing. Things sometimes go wrong, but this is by no means a disastrous pre-season for Ferrari - in fact it's the best I can remember for several years. They aren't going to leave the sport based on one day with 69 laps.
Grosjean is now back in the pits and with that super-soft run now has a total of 102 laps for the day (not to mention the fastest time by 0.847s)
@melon: Don't write the entire season off based on one test day
We're in the final hour of this week's test now
Alonso's manager Luis García Abad has told Spanish TV that his driver was not unwell before today's accident, dispelling rumours that he may not have been fit to drive. Alonso will be kept in hospital for between 24-48 hours for observation, according to Abad.
Kvyat, Nasr, Rosberg and Bottas are the only drivers on track at the moment. The Red Bull and Mercedes are on medium tyres and the Williams and Sauber are on hards. Unlikely they'll improve on their times.
Impressive stuff from Rosberg, who sets a 1:24.584 on medium tyres to go second fastest. Grosjean's time, by comparison, was on the super-softs.
Hamilton's pole lap from last year (on mediums) was a 1:25.232. So Rosberg's time is 0.648s faster but probably with more fuel. However, Hamilton's time was set at the fifth round of the championship so an Abu Dhabi-spec W05 would have been quicker than 1:25.232. Rosberg's is a good time but still masked by fuel loads.