The start of the Formula 1 Singapore Grand Prix is under threat after heavy, torrential rain fell in the build-up to the race.
Planned for an 8pm local, 2pm BST start, a cloudburst bubbled up and moved across the track.
Cars have been unable to go out on their re-con laps to the grid, with the starting procedure delayed.
The Safety Car has toured the track on exploratory laps, with the rain easing to allow marshals out on circuit to start clearing puddles and rivers that have formed.
Following the abandonment of the 2021 Belgian Grand Prix, the rules for situations such as these were tightened up after half-points were awarded for just one lap behind the Safety Car.
Now, if more than two laps are completed but less than 25%, points will be awarded in a 6-4-3-2-1 manner, with half points for 25-50% race distance.
Should 50-75% of the planned race distance be completed, points will be dished out at about 75% of full share.
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