Patrick Frank: How many F1 drivers are wine connoisseurs? 

Pleassseee don't leave me here to talk to myself. I dread to think what I'll be rattling on about in an hour.

Message from race control: "The medical helicopter is not able land at the designated hospital in Shanghai. Delay is expected to be a minimum of 30 minutes."

The haze has really descended over the circuit now and visibility is very, very low. That will be the reason for the helicopter not being able to fly.

Just seeing shots now of said medical helicopter, sitting on its pad, its rotors not spinning.

The handful of cars that did make it onto the circuit are back in the garage and the drivers have climbed out of the car.

I guess if that medical helicopter does not get up and running then no one will be able to head out.

I'm afraid what that will mean is - if you are in the UK - that you have got up solely to read me wittering away for 90 minutes.

Red flagpublished at 03:05 British Summer Time 7 April 2017

03:05 BST 7 April 2017

Four minutes in and we have a red flag. The reason? Because the medical helicopter cannot operate.

Andrew Benson
Chief F1 writer

For the second race in succession, Ferrari third driver Antonio Giovinazzi is subbing for Pascal Wehrlein at Sauber. The German blames a lack of fitness caused by time off training while recovering from a back injury sustained in the winter and says he does not want to race until he is able to do the whole grand prix at peak performance. But it is fair to say his decision is causing widespread bemusement. Generally, drivers race whether they are completely fit or not. 

This is the first time anyone can remember an apparently healthy driver actively choosing not to race because he feels a little bit physically undercooked. There are all sorts of conspiracy theories flying around but Mercedes, who own his contract, Sauber and Wehrlein insist that there is nothing sinister going on and it is what it is being presented as - he simply has to take his time to get back in shape. But still people are wondering if there is not more to it than meets the eye. 

“I really hope that there is nothing more serious with him," said Force India driver Sergio Perez. “If I was in that position, which remember I was after my accident in Monaco in 2011, as a racing driver you're not really bothered if you're not 100% to do the race. I would be in the car, that's the best way to get back up physically. Every driver and every person is different, so I respect his decision."

Image source, AFP

Rod Pool: Good afternoon all from Bolivia. Looking forward to your usual excellent commentary this weekend. 

Antonio Giovinazzi is in the Sauber once again because Pascal Wehrlein has decided to skip this race to continue to build up his fitness.

Great racing name is Antonio Giovinazzi, up there with Mario Andretti for me with the way it rolls off the tongue.

Andrew Benson
Chief F1 writer

It is early days but Melbourne provided some hints about the various strengths and weaknesses of the Mercedes and Ferrari cars. Lewis Hamilton was asked to expand on them in China. “Our car is longer so it’s probably more stable in the higher-speed corners,” Hamilton said. “Theirs is shorter, more nimble. in the middle slower section they will be a little quicker i think in the longer higher speed sections  I think we’ll be better and also on our tyres. But it is only one race. Time will tell.” 

Hamilton’s remarks actually contradicted one example of comparative performance in Ausrtralia -  the Ferrari’s better tyre usage. He added that the length of the Mercedes - which will help give it more overall downforce - gave him some concerns for some races later in the season. “It is something like 120mm longer than Ferrari. In Monaco, how I will get it around the tight corners I don’t know.”

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The rain has stopped but the track is wet. A good chance to test the Pirelli tyres in these conditions at a race weekend with the only previous wet running the drivers have had in 2017 during pre-season testing in Barcelona.

Fernando Alonso says he is not yet ready to be spending his Sundays in a supermarket. Retired world champion Nico Rosberg, meanwhile, seems quite content to hit the shops. 

What would you do if you were an F1 driver and quit the sport? Let us know #bbcf1, external

Andrew Benson
Chief F1 writer

Sebastian Vettel was in full ‘one-race-at—a-time, keep-your-feet-on-the-ground’ mode on Thursday, keen to keep expectations in check after his impressive victory in Australia. 

“After one race it is easy to say this year is better than last year but it is only one race,” he said. 

“A lot of things have changed, people are more comfortable throughout the whole team and the work going in is a lot more targeted and hopefully we can keep it up.” 

It was left to Fernando Alonso to state what many believe: “It definitely seems like they are contenders but last year they were also en route for the victory without the red flag I caused, so let’s wait and see. But hopefully we can see a more interesting championship this year. The people will be delighted if there is a little bit of a fight at the front.”

As you can see it is not a pleasant day at all in Shanghai. More of the same throughout the weekend? Our weatherman Ian Fergusson has the forecast...