For most of the US Grand Prix, it looked as if Lewis Hamilton would have to wait until Mexico to clinch his third title, until a mistake by Nico Rosberg sealed the fate of the championship. Adam Cooper analyses the key moments of the Austin race.
After endless hours of torrential rain in Austin a miracle happened on Sunday. During the lunch break the rain began to ease off, before finally stopping. And at around 1.25pm, just five minutes before the pit lane opened for the start, we even saw the sun trying to break through the clouds, and a few little patches of blue sky. The timing could only have been ordered by some almighty power. It was Bernie weather...
The improving circumstances guaranteed us that we would have a proper start rather than one behind the safety car, and that we would soon have a drying track – with all that entailed.
Given that even a few hours earlier Q3 was called off, and at times during the weekend it looked like we might not have a race at all, what followed was extraordinary. We enjoyed one of the most exciting afternoons the sport has seen in years, and we had a World Championship that was formally concluded only when the leading cars had taken the chequered flag.
It was F1 at its very best, thanks to a perfect storm – no pun intended – of the wet start and drying track, a lack of race preparation over the weekend, and a series of incidents down the field that neutralised the race and ensured that the fortunes of those contesting the lead, and indeed the championship, ebbed and flowed. Even Bernie could not have scripted this one.
That lack of pre-race preparation was the key factor. Drivers ended up using as many as three types of tyre – the inter, medium and soft – that they didn't try at all before the race, and that uncertainty of how things would unfold kept everyone on their toes throughout, with conditions favouring first one chassis/tyre combination, and then another, and the balance shifting again through the life of those tyres.
"It was very difficult," Toto Wolff said when asked by Motorsport.com. "So many decisions to make, so many marginal calls, with the virtual safety car and safety car. I guess, at the end, we had the luck on our side, Lewis had the world champion's luck on his side with that Kvyat incident. But it was super tough."
A full story how things unfolded, and how both Red Bull and Ferrari played a major role in making it such a memorable afternoon, would probably fill a book. So here are six key moments in the Hamilton v Rosberg battle:
1. The start – advantage Hamilton
We had a damp track, intermediate tyres and little knowledge of bite points, so an interesting start was guaranteed. And at Turn 1 Lewis showed he meant business by muscling Rosberg off the track, just as he did at Suzuka.
He got away with it, and Mercedes got away with two undamaged cars, but the bottom line was that Lewis was now safely in front.
That opening stint proved to be thrilling, as the Red Bulls showed their pace and Ricciardo worked his way first past Rosberg, and then past Hamilton.
The tyre situation was fascinating as well as the inters wore out, and drivers struggled to find lap time. But it was still too early for the change to slicks. The advantage then swung towards Rosberg and he began pushing Lewis hard. This was getting interesting...
2. The change to slicks – advantage Rosberg
Nobody had any hard information from practice about the crossover point to slicks, although Pirelli had a ballpark lap time of 1m48s. Rather optimistically Williams and Sauber took advantage of drivers pitting after first lap incidents to put slicks on straight away, and for both Bottas and Nasr, it was a disaster of epic proportions.
As the race progressed everyone faced an extremely tricky decision, given that the intermediates were on their last legs, but a change to slicks even a lap or two too early could lead a drop in temperature that would be hard to recover. It was Sauber who showed when the right time had finally arrived when Marcus Ericsson came in on lap 16 and began to set fast sector times.
Jenson Button followed a lap later, and by then the leaders knew that it was time to come in. At Mercedes Lewis was given priority, and he pitted on lap 18, along with Sebastian Vettel and others further down the field.
Rosberg and both Red Bull drivers came in on lap 19 and, when the stops had shaken out, Ricciardo still had his lead, albeit a reduced one, from Rosberg, Daniil Kvyat and Hamilton.
It was quickly obvious that the Red Bulls didn't have the pace on slicks. In contrast, Rosberg was flying, and he was soon in the lead and pulling away. Hamilton struggled initially, but then when his tyres came on song he picked up speed and worked his way into second. But Nico was long gone.
3. The Ericsson safety car – advantage Hamilton
Having shown everyone the way with the change to slicks, Ericsson then turned the race on its head when he stopped on track. A virtual safety car quickly turned into a full-on safety car, and Rosberg's lead over Lewis – which was as high as 12.1s – instantly evaporated.
Neither Mercedes pitted, as their tyres were less than 10 laps old, but Vettel took a fascinating punt by going for mediums and opening up the possibility of getting to the end without another stop. That gave Mercedes plenty of food for thought.
Nico stayed ahead at the restart, but Hamilton was now fully on song, setting fastest laps as he pushed him hard.
4. The Hulkenberg virtual safety car – advantage Rosberg
After barely five laps of racing Hulkenberg collided with Ricciardo, and we got another virtual safety car. The challenge teams face now is that they never know if and when a VSC will turn into a full one, and they have to factor that in to any strategy moves.
It was at this point that Mercedes split the strategies, a rare move indeed for a team that prides itself on not favouring one driver or the other, but one that added extra intrigue to the afternoon.
Matters were complicated for the team by Vettel's gamble as Mercedes now had to worry about the Ferrari man, and not just how the HAM and ROS fight would unfold.
The key thing about a VSC is that even if it doesn't turn into a full SC, you lose less by pitting than you would stopping under green flag conditions, so it's often worth a punt. Thus Rosberg came in and made the tyre change that would get him to the flag.
Hamilton could have been stacked behind him, as Red Bull did with its drivers. But he stayed out, in effect to ensure that Mercedes could cover Vettel one way or the other. As Wolff noted, Mercedes also had the opportunity to study Rosberg's tyres, which helped to gauge how things would unfold for Lewis.
It would be interesting to know if the team would have changed its mind and pitted Lewis anyway had the VSC period been extended, or even turned into an SC.
5. The Kvyat safety car – advantage Hamilton
At the resumption after the VSC Lewis was 5s clear of Vettel, and 8s ahead of Rosberg, the latter with brand new tyres. The German duo could both get to the end, but there was now an obvious risk that Lewis would have to make a stop for fresh tyres under green, and that would prove expensive.
There was much to think about, as Hamilton's engineer indicated: "We need to find another 10 seconds to Vettel, we are not sure we can do it on this tyre set..."
By lap 42, Hamilton was just 6.2s ahead of his team mate, his tyres running out of useful life, and he still had 16 laps to run. It didn't look good.
Then it all changed once more as Kvyat crashed and brought out the SC. The timing could hardly have been better for Lewis – and he dashed into the pits. He gave up his lead but instead of losing a ton of time pitting under green, he sat right behind Rosberg in the queue, with tyres that were five laps younger.
Meanwhile, Vettel also took advantage of a free stop, and while he lost a spot to Verstappen, it was worth it for the new rubber.
6. The last restart – 10 laps to win the world championship...
When the track went green with exactly 10 laps to go, we were poised for a fabulous conclusion to the race. And Lewis was up for it.
But in the end he didn't have to find a way past – this sprint to the flag was barely under way when Rosberg invited him through, running wide.
Intriguingly, offering a possible explanation for Rosberg's mistake was none other than Hamilton, albeit one that also hinted that the Briton had done a better job: "I had the same issue as he did. Obviously I didn't go off, but I had a similar issue of wheelspin at that one point where I was changing a switch out, that same corner, and nearly lost it so I understand and sympathise with him."
The sympathies won't be much of a consolation for Rosberg, who could have scored one of the greatest wins of his career, one that would have gone a long way to silence any criticism of his form relative to Hamilton this year.
Instead the German found himself trying to keep Vettel at bay for second, and in by doing so he guaranteed that Hamilton wouldn't have to wait until Mexico to celebrate his title.
The reactions we saw from both drivers post race told their own story and Rosberg had every right to look a little distracted as he pondered how his day had unfolded, eventually coming to a conclusion that he was still rather upset at the Turn 1 clash.
"Lewis came on the radio and said it wasn't on purpose," said Wolff of the Turn 1 incident. "I think it's something we are going to talk about in a couple of days, but this is a moment to celebrate a World Champion who deserves to be World Champion, and then once emotions have cooled down, we should discuss it."