Mercedes boss Toto Wolff says reliability will play "a fundamental part" in the openings races of the 2020 season.
Formula 1 will kick off its long-awaited campaign on July 5 in Austria, an opening round that will be followed by another race at the Red Bull Ring a week later and six events unfolding thereafter into early September.
Given this year's reduced schedule due to the coronavirus pandemic, many drivers have highlighted the importance of consistency and the need to avoid costly mistakes.
But a similar premise applies to the teams, and especially Mercedes which encountered power unit issues earlier this year in pre-season testing in Barcelona.
And as a reminder, the Silver Arrows squad's efforts at the Red Bull Ring last year were undermined by engine cooling issues.
"First of all this new calendar and the coronavirus throws some new challenges at us," Wolff said, quoted by Crash.net.
"I think reliability is going to be a fundamental part of the opening races.
"The cars have come out of the container straight from Australia. There is not a lot of time for them on the dynos. We will be using every session to learn.
"The reduced race calendar is a challenge for everybody and again, I think that the team that has the quickest car and the most reliable package will win the championship."
Wolff says the speed of its rivals in winter testing, including Ferrari's relative lack of performance, offered only a very partial indication of the potential pecking order.
The Austrian is therefore keeping his expectations in check until everyone hits the track in Spielberg, insisting that more convergence has likely taken place on the engine front between F1's four manufacturers.
"Last year’s Ferrari power unit was much more powerful, but we haven’t seen it yet," he said.
"Only in a qualifying session and the race is everyone really going to show their hand, and we haven’t seen that.
"I’m obviously always on the pessimistic side – we need to catch up, we need to come out with a reliable and powerful and drivable engine and I hope it’s enough.
"But I also wouldn’t discount Honda and Renault, I think pretty much every single power unit supplier is pretty much on par now."
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