Despite all their talk of concern at high tyre degradation yesterday, the Mercedes duo didn't appear to bothered this morning, both out-pacing their nearest rival - Ferrari's Kimi Raikkonen - by a second.

Indeed, such was the confidence, whilst rivals were finally switching to the option rubber, Nico Rosberg and Lewis Hamilton were already performing back-to-back pit stops.

Behind the leading the leading trio, it was almost a case of total symmetry - and this the same week that the movie Noah is released. Whilst Fernando Alonso could only manage seventh, and Nico Hulkenberg spoiled the party by splitting the Red Bulls, the order behind read Williams, Toro Rosso, Sauber, Lotus, Marussia, Caterham and, er... McLaren.

Following problems with a sensor on Kevin Magnussen's car in yesterday morning's session, today both cars were afflicted. Basically, the sensor is (falsely) picking up on a problem and shutting the engine down. Speaking shortly after this morning's session, team boss Eric Boullier suggested that if it cannot be resolved in time the Woking duo might not be able to run this afternoon. A total volta-face following the impressive performance in Melbourne.

That said, as is often the case in Malaysia, the weather gods might have thrown a spanner in the works. The rain that was expected during FP3 has finally shown up just forty-five minutes before Q1 gets underway. Hopefully it will stop in time, and the humidity will soon dry the track, but there is the threat of further rain later.

Taking the Mercedes duo out of the equation and using Raikkonen as the benchmark, the drivers from third down to eleventh were covered by 1.026s, indeed, Vergne and Sutil (14th and 15th) were within 1.3s, so it's all pretty even out there.

In fact, the rain doesn't ease, it gets worse, much worse... it is a typical Monsoon deluge, to the extent that Q1 is delayed by fifteen minutes. Air temperature is 24 degrees C, while the track temperature is 30 degrees.

Of course, with this session starting at 16:00 (local time) - thanks Bernie - there is concern at the failing light, visibility already compromised by the dark storm clouds.

Inevitably, the start of the session is delayed by a further fifteen minutes though the rain shows no sign of easing.

At 16:20 the Safety Car heads out to check the conditions. Unsurprisingly the session is delayed by a further 15 minutes.

According to Twitter (where else?); qualifying at Japan 2004 and 2010 was postponed until Sunday morning because of rain, while Australia 2013 was postponed after Q1 was completed.

The rain starts to ease but it all depends on when it will stop and how quickly the track will dry. Replay of Safety Car shows a lot of standing water. Then there is the fading light to consider.

Official radar says that while the rain is easing there is further "intense activity" around 4km away and heading in. Nonetheless, mechanics are in the pitlane with their fans attempting to dry the pit slots as much as possible.

Despite the fact that the rain has stopped and that there are clear patches of blue, the start is delayed by a further 5 minutes.

Following a further check, the start of the session is confirmed for 16:50.

With the threat of further rain there is sure to be clamour to get on track... which, is already pretty dry.

At the end of the pitlane, anticipating the green light, is the Mercedes duo, with over two minutes still to go. "We do expect rain," Hamilton is told, "so do make your early laps representative".