The only two drivers who have yet to set a time are Lewis Hamilton and Nico Rosberg. Both Mercedes remain parked in the garage with 30 minutes gone and 30 minutes remaining.

Image source, Getty Images

Today marks 27 years since Gerhard Berger won the 1987 Japanese GP, ending what was then a two-year winless streak for Ferrari, as opposed to the 18-month winless streak they currently endure. Judging by the pace of that car, that miserable streak is set to continue for a while yet.

Daniel Ricciardo heads out and immediately pumps in the quickest time with a 1:39.693, one tenth quicker than Williams' Valtteri Bottas.

PhilSlocombe: Lewis has the momentum over Nico. A win on Sunday (5th in a row), should see him go on to win the WDC, subject to reliability.

Justice Kavahematui: Pound for pound @LewisHamilton has shown that he is a better driver than Nico. Let's hope they both get a reliable machine.

Have your say using the #bbcf1 hashtag, text 81111 (UK only) or leave a comment on the BBC Sport Facebook page.

Felipe Massa dips down into the 1m39s as he goes quickest with a 1:39.820. one second quicker than Kevin Magnussen. Jenson Button is third, a few thousandths back, with Valtteri Bottas fourth and Force India's Nico Hulkenberg.

It's much cooler in Austin now than it's expected to be later on for qualifying, so that may explain why the bigger teams are choosing not to go out.

Lewis Hamilton returns to the pits, having completed two installation laps. His team-mate Nico Rosberg hasn't been out yet - and he's not even in his car. There's a bit of work going on at the rear. The Red Bulls of Sebastian Vettel and Daniel Ricciardo are sitting tight for now, too.

Kevin Magnussen sets the early pace, the Dane clocking a 1:41.567, four tenths quicker than Force India's Sergio Perez.

Image source, Getty Images

Lewis Hamilton does a practice start before heading out on track for his first foray under bright blue skies in Austin. His Mercedes team-mate and title rival Nico Rosberg is staying put in the garage for now.

Andrew Benson
Chief F1 writer

"The collapse of the Marussia and Caterham teams has heighted an existential crisis that has been going on all season. Force India's deputy team principal has been very outspoken in Austin, accusing the big teams and commercial rights holder of an 'agenda' and saying the sport is not sustainable. The bosses of the big teams agree something needs to be done, but point out that criticisms of the split of revenues are misguided, saying that of course the more valuable brands such as Ferrari should receive more money because they are more important for the sport.

"Mercedes team boss Toto Wolff said teams had an 'entrepreneurial responsibility' to only spend what they had. He admitted that 'if we could reinvent F1 on a white sheet of paper maybe the distribution model would be a different one', but added: 'We need to not push the panic button but to protect the smaller teams. We need to stick our heads together and decide what we do.'"

The lights at the end of the pit lane have flicked to green which can only mean one thing. It's time for final practice!

Jennie Gow
BBC Radio 5 live pit-lane reporter

"Daniil Kvyat will take a 10-place grid penalty for changing his engine. It will be his seventh, when only five are allowed. This follows Red Bull's Sebastian Vettel's own penalty - starting from the pit lane - for an entire new engine. Both cars use Renault engines."

BBC Radio 5 live sports extra

James Allen is up and running in the commentary box, with Jennie Gow and Tom Clarkson down in the pit lane. You can listen on BBC Radio 5 live sports extra by clicking the link at the top right of this page.

Time for some title talk... Lewis Hamilton leads Nico Rosberg by 17 points, but there are still 100 points remaining, with 50 of those available to the winner in Abu Dhabi thanks to the double points. The title cannot be won this weekend in Austin. But if results go his way, Hamilton could claim it next weekend in Brazil, scene of his 2008 world championship triumph.

Andrew Benson
Chief F1 writer

"Formula 1 trialled the new 'virtual safety car' idea after both Friday practice sessions, a way of controlling the speeds of the cars at times when there is a recovery vehicle on the track but officials think it can be cleared quickly enough not to need a safety car. It is aimed at preventing the circumstances that led to the accident that left Jules Bianchi with severe head injuries in Japan. But while the new system, which gives drivers a target lap time to stick to, as generally welcomed, all agreed it needed some work.

"McLaren driver Jenson Button said: 'There are positives and negatives. When you are wheel-to-wheel you can't just hit the brakes to get the speed down like we are now in practice and you only have a certain amount of time to do it. So in that respect it's very tricky.

'With the way the safety car boards are now and with the lap we do when there's no safety car, you can dip below the speed and you get away with it because as long as you cross the finish line positive you're OK. But with this system you always have to be positive but you want to be as close to zero as possible because you could lose two seconds to the car in front. If you drop below and the restart happens you get a 10-second penalty so it's very, very tricky.'"

Image source, Lewis Hamilton on Twitter

Lewis Hamilton appeared on America's popular Today Show before this weekend. He got just over a minute and a half of airtime.

Sarah Lazarovic, on the segment before him, got four minutes. Her claim to fame was that she apparently managed to go 12 whole months without shopping for clothes or shoes.

Formula 1 has plenty of work to do if it is to make an impression on the American public.

These live texts are always a lot more enjoyable if you, our dear readers, get involved. So where does Austin stand in terms of the great F1 race tracks?

Do you think Lewis Hamilton will beat Nico Rosberg to the F1 title? Will Formula 1 lose more teams, after Caterham and Marussia went into administration?

Tweet us using the #bbcf1 hashtag, text 81111 (UK only) or leave a comment on the BBC Sport Facebook page.

Two teams who won't be in action this weekend are Caterham and Marussia. The two outfits are in administration and fighting for survival. Caterham's Marcus Ericsson and Kamui Kobayashi are in the paddock, working on saving their own F1 futures, as is Marussia's Alexander Rossi. Incidently, Rossi will be in the BBC Radio 5 live commentary box for Sunday's race.

Andrew Benson
Chief F1 writer

"If there was a sense after Lewis Hamilton's victory in the Russian Grand Prix, his fourth in succession, that he was beginning to lay one hand on the world championship trophy, Nico Rosberg has indicated here he is still up for a fight. There was nothing to choose between the two Mercedes drivers on Friday, Hamilton fastest by just 0.003secs.

"'It is looking very close between me and Nico,' Hamilton said, 'so I am expecting a very, very tough battle in terms of us racing particularly, but I am excited, I am ready for it.' Rosberg added: 'Very tight - a bit as usual. Three thousandths but I have them in my pocket. I know where they are. The car is really quick here again. It is a pleasure to drive. So I am looking forward to the rest of the weekend. It looks like it is going to be a battle between my team-mate and me."

Today, the high point is qualifying but before we get to that, we've got the small matter of third and final practice. That'll last one hour and provide teams with a final chance to gather long-run data before doing a qualifying-simulation run towards the end of the session. It all kicks off at 15:00 GMT.