SUZUKA, Japan -- Since the Singapore Grand Prix three races ago, there has been an inevitability about the collapse of Sebastian Vettel's title campaign. Poor qualifying performances led to strategic errors, which in turn bred more mistakes and cranked up the pressure.
As the mistakes snowballed, the gap in points to Lewis Hamilton got bigger and the burden on Ferrari to succeed grew heavier. In the space of those three races, the persistent errors shrunk Vettel's championship chances from slim to microscopic and, just when he needed it most, Ferrari's performance advantage disappeared. Ferrari will now return to Maranello ahead of the final four rounds of the season and, as it did last year, will start dissecting what went wrong.
A gamble against the odds fails to pay off
If Ferrari is looking for a case study in spiralling decline, it need look no further than its Japanese Grand Prix. From the very first session of the weekend it was clear Mercedes had a performance advantage over Ferrari, and although that gap closed in FP2 and FP3, in normal circumstances, the race was Mercedes' to lose.
Rain in the air for qualifying presented an opportunity for Ferrari to force a result on Saturday, but to do so they would have to gamble. Ahead of Q3 the rain radars on the pit wall were peppered with blue dots, but the track itself remained dry. Normal operating procedure is to start the session on the tyres that suit the circuit at that moment -- after all, wet tyres can always be fitted if the rain comes later -- but Ferrari took a risk and went for intermediates on a dry track. As it happened, the rain held off, Vettel had to return to the pits and was then sent out on slicks just as the conditions worsened to set the ninth fastest time.
A good start to the race and some bold overtaking moves in the opening laps meant Vettel started making up for the mistake immediately on Sunday and was fourth behind Max Verstappen at the start of lap eight. He knew there wouldn't be many opportunities to pass the Red Bull and he knew he had to be aggressive to make it stick, so when a gap opened up on the entry to Spoon corner Vettel went for it...
Had he qualified in position he wouldn't be making this decision, but Saturday's mistake had raised the stakes and Vettel now needed to win big. Just like Saturday's tyre choice, there were risks and rewards at stake: A successful overtaking move would move Vettel up to third and give him a chance of taking precious points off the Mercedes ahead, but a botched move could drop him to the back of the field.
"How many times you can afford to wait?" he said when asked if he considered not making the move. "Obviously, I am not just racing him, I'm racing also the guys in front ideally. His battery was derating, I saw the light flashing, I had saved up my battery on the way up through the Esses, trying to stay close, had a good exit from the hairpin and had a big tow through turn 12 and was side by side when we hit the brakes and turned in."
The resulting collision dropped Vettel to the back of the field and out of contention for a podium. He battled back to sixth, but the result means a Hamilton-led Mercedes one-two victory at the next round in Austin will rule Vettel out of the championship completely. He took a risk on Sunday, it didn't pay off, but given the way things have gone at the last three races, you can't blame him for trying.
Has Mercedes got faster or Ferrari become slower?
In isolation, both Ferrari's tyre gamble and Vettel's botched overtaking move look foolish, but they were borne out of an increasingly desperate situation. Since Singapore, Mercedes has gained the upper hand in performance and while Ferrari's errors during that same period have accelerated Hamilton's charge towards a fifth world title, the underlying swing in performance had already set the wheels in motion.
According to team boss Toto Wolff, the turning point for Mercedes this year was the Belgian Grand Prix. Vettel won that race after getting a run on Hamilton on the opening lap and the result not only underlined Ferrari's power advantage but also highlighted Mercedes' weaknesses. Throughout the weekend Hamilton had struggled for grip out of the first corner and the final chicane at Spa-Francorchamps, and with the flaw exposed Mercedes honed in on fixing it.
"Every race since Spa we have brought an upgrade onto the car," Wolff explained. "Every millisecond adds up to a more considerable amount of pace and we have been able to translate that into real track performance. Sometimes wind tunnel data or any kind of data that you are trying to extrapolate doesn't translate into the expected amount of lap time, but in these races it has.
"But no development would have brought 1.5s in performance. What brought the difference was the understanding of how to run the tyres because they are the single largest denominator and this is an exercise where we have invested a lot of time. Spa, Turns 17, 18 and La Source, explained why."
Armed with a better understand of how to gain grip out of slow-speed corners, Mercedes surprised the paddock with its pace two rounds later in Singapore. On a track where the team had traditionally struggled, Mercedes was suddenly back in form and Hamilton's qualifying lap proved to be a key turning point in the season. Clearly a step had been made by Mercedes, but there was also a suspicion that Ferrari had fallen back.
Mercedes had often referenced Ferrari's impressive straight-line speed as the main reason for the Italian team's advantage earlier in the season, and GPS traces showed that the Ferrari was gaining a significant advantage on sections of the track where it was deploying power from its hybrid system. Speculation about how Ferrari was running the electrical side of its power unit had been rife since the start of the year and its battery had been the subject of an FIA investigation between the Azerbaijan and Monaco Grands Prix.
It emerged after Singapore that the FIA had introduced a new sensor to the Ferrari's battery and that fuelled the belief that it might be linked to the drop in performance the team had experienced. The theory was backed up by another lacklustre performance for Ferrari in Russia, but in Japan, team boss Maurizio Arrivabene was quick to deny the rumour.
"It's nothing to do with the speed in the straights, because in Singapore and in Russia, we were quicker," he told RTL. "We were ahead in Singapore and as I said before in Russia we were nearly like our main competitors."
The FIA backed up Arrivabene's comments on Sunday, but only after the Ferrari boss had displayed anger at the news of the new sensor leaking out.
"There's a drop in form, and I think there's some speculation that it's due to this magic sensor that we've made them put on," FIA race director Charlie Whiting said after the race. "I'm not going to go any further on that, but I would say from an engine performance perspective, we don't agree with what is being suggested."
Wolff, who had been keen to point out Ferrari's advantage earlier in the year, was also reluctant to make any suggestions about changes to his rival's engine.
"We are still seeing a very powerful Ferrari engine," he said. "Clearly it is still a benchmark, but it hasn't been as much of a differentiator recently as it has been at the beginning or the middle of the season. I don't know why."
The only one who hinted that the rumours might contain a grain of truth was Hamilton. He had previously referenced "trick things" going on under the Ferrari bodywork at the Belgian Grand Prix and on Sunday after the Japanese Grand Prix gave a gentle nod towards a change since Singapore.
"We do have an idea of what has happened but it's not for me to discuss," he told Brazilian broadcaster UOL Esporte when asked if it was a step down in performance for Ferrari or a step up for Mercedes. "It's something we thought was happening ... but anyways, we have not brought updates here and we only had less the 0.05s in the last race in Russia."
Without access to Ferrari's power unit data it is impossible to read too much into the above comments either way. But in a season in which Ferrari once held the performance advantage and failed to make the most of it, it is easy to understand why this championship is no longer going down to the wire.