Aston Martin has identified the origin of Lance Stroll's retirement from last weekend's Saudi Arabian Grand Prix although it has yet to determine the root cause of the failure.
Having launched his race from P5 on the grid, Stroll cycled through a strong opening stint in fourth place before switching from the medium to the hard compound tyre on lap 13.
But three laps after resuming his charge, the Canadian was ordered by the Aston pitwall to stop his car, which he duly did, pulling off the track at Turn 16.
"We were just losing power every lap, like six, seven laps kind of thing, just a second and a half every lap and eventually it was game over," said Stroll after the race.
"They were [applying the fire extinguisher] on the brakes, but there was some smoke from the engine."
After the race, when Stroll's car was brought back into the garage, an early diagnosis pointed to the AMR23 suffering an energy recovery issue, although it was unclear at that time what had caused the problem.
"It is a real shame that Lance was forced to retire early with an energy recovery issue, the cause of which is still being investigated, because he had strong pace and would surely have scored big points tonight as well," said Krack, alluding to Fernando Alonso's remarkable run to third, although the official result was only confirmed several hours after the race.
Stroll, who was still nursing his right wrist in Saudi Arabia, was understandably disappointed to miss a second opportunity this season to score some good points.
"It was disappointing to retire from the Grand Prix after such a promising weekend," he said. "I had a great start and really enjoyed overtaking Carlos [Sainz] around the outside of Turn 13.
"It is not the result we wanted, but we leave Saudi Arabia knowing that we have a very competitive car and we will pick up the fight next time out in Australia," concluded the Canadian.
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