The disaster that befell Ferrari at the start of the Singapore Grand Prix may have done untold damage to Sebastian Vettel's bid for a fifth world title.
Marina Bay was the one circuit remaining in the title fight where Ferrari were staking everything on being significantly faster than Mercedes.
All the hard work that led to a brilliant pole position for Vettel was wiped out by the collision between the two red cars and Max Verstappen's Red Bull at the start.
So now the German has a mountain to climb, 28 points adrift of race winner Lewis Hamilton with six races left.
Vettel recently ventured the opinion that Ferrari, traditionally better than Mercedes on high-downforce tracks, no longer have anything to fear on any type of circuit.
And now he must be praying that opinion becomes fact - since he'll need to win the next four, assuming Hamilton is runner-up, just to draw level.
MALAYSIA: ADVANTAGE MERCEDES
Malaysia is next, and Hermann Tilke's first Asian design venture comprises a lot of long, fast and flowing corners which require a compromise between high and medium downforce. Overall, the advantage should be with Mercedes there, though the unpredictable weather can add a new dimension.
Overall, the advantage (at Sepang, the next race on Oct 1) should be with Mercedes, though the unpredictable weather can add a new dimension (to the title race).
Suzuka follows a week later, and this is a mixture of slow-, medium- and high-speed corners. It requires high downforce, and thus tends to favour Ferrari.
UNITED STATES: TOSS UP
Austin, in Texas, has always been a happy hunting ground for Hamilton, who has won four of the five races held there, Vettel taking the other in 2013.
It's an amalgam of many other tracks, borrowing a slow corner here, a set of fast sweeps there. The disparate nature of the corners makes the choice of downforce difficult for the engineers - the fast ones are quicker than Spa, the slow ones slower than Hungaroring.
Mexico has the shortest period of full-throttle running of the remaining tracks - 47 per cent compared to 60 plus, yet combines slow and very fast corners and requires only slightly more downforce than Monza.
Brazil has the shortest lap on the calendar, but the mix of two long straights and a lot of high-energy corners generates another compromise on downforce, especially for the long climb out of the last corner and past the pits, where much of the overtaking occurs.
ABU DHABI: MERCEDES
Abu Dhabi, also a Tilke track, has some slow corners but a very long - 1.2 km - straight, which obliges teams to run medium downforce. Mercedes introduced significant updates in Belgium and Italy and Hamilton won both, as expected, since they were on high-speed, low-downforce tracks.
But at Spa-Francorchamps, the Briton admitted that he would not have won had Vettel started from pole - and the fact that the German was only 2.3 seconds adrift indicated Ferrari's improvement.
Mercedes have upgrades for Malaysia and Japan, to improve performance on medium-speed, high-downforce tracks.
From the start of the season, Hamilton has maintained that each team's rate of development, especially when their design engineers back home are now working flat out on the 2018 models, would be the deciding factor in the title fight.
Red Bull could yet play the role of spoiler by taking points off either of the two teams - as their Singapore performance indicates yet again just how much progress they have made since Adrian Newey came back into the design team at the start of the European season.
It would be most unwise to suggest that the title battle is over, but assuredly Singapore has made things an awful lot tougher for the man who led it for so long.
Just as Hamilton said he needed a miracle in Sunday's race, so Vettel will be praying for one in those that remain.
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