BMW driver Maximilian Gunther ended up with the fastest time of the 24 drivers taking part in this week's three-day Formula E pre-season test at Valencia.
Gunther's time of 1:15.087s was set after just 17 laps of running on Friday afternoon. He subsequently triggered an early end to the day's track activity when he stopped at the first chicane with five minutes left on the clock.
Dragon pair Brendon Hartley and Nico Muller, together with Mercedes driver Stoffel Vandoorne, also sparked red flags in the final hour of Friday's session.
Gunther duly finished the day a tenth quicker than Mahindra Racing's Pascal Wehrlein, who had been the fastest driver in the morning runs.
Earlier in the day, Nissan e.dams' Sebastien Buemi won the second 'test race' of the week by 1.698s over 30 laps from Porsche’s Andre Lotterer who led at the start.
However the week as a whole proved a subdued start for Mercedes, which is joining the all-electric championship this season for the first time as a manufacturer.
Vandoorne was only 20th fastest across the week, setting his best time of 1:15.736s on Friday morning. His team mate, Formula 2 champion Nyck de Vries, was just behind the Belgian in the week's timing summary with a best effort of 1:15.916s.
"The first two days of testing this week were tough for us," explained Mercedes-Benz EQ Formula E team principal Ian James.
"There were some challenges to overcome that we had not anticipated. It was unexpected, to be honest, but we found the right solutions. It just goes to show how important these test outings are in the run-up to the season.
"We were consistent when conducting our own private tests and found some stability. We must now ensure that we can achieve that again during the first race weekend.
"[But] we've finished Friday's test on a positive note. I think we've created a sound basis on which to build, so that we can continue to develop during the season."
"We're obviously not completely satisfied after this test week, but that's precisely what testing is for," echoed Vandoorne.
"We've ticked off quite a few points on our to-do list, but there's still plenty to do before the season opener in Saudi Arabia [on November 22].
"At the same time, I am happy that we are finally racing again. We have been testing for a long time now and the feeling is good," he commented. "After the long break, I'm really looking forward to getting back into the car and competing in actual races."
"Everything is in place for us to mount a serious challenge, but we have to get it all together. This is by no means an easy task in Formula E. Let's wait and see what happens next."
De Vries was held back by limited track time, with an accident on Wednesday afternoon leaving him sidelined for the rest of the day.
"Unfortunately, I made a mistake in the chicane and lost a lot of time on the track," said the 24-year-old Dutch driver. "That, along with a few other difficulties, virtually cost me a whole day.
"That's why it was very important to have a flawless day today, during which I was able to put in a lot of laps and gain further experience.
"[Friday] morning was very positive in this regard, and the afternoon also was very interesting with regard to the race simulation. It was a pity that there were so many interruptions on the way, but that's all part of racing."
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