Mercedes boss Toto Wolff has revealed that a generator failure on the grid was the cause of the early struggles Valtteri Bottas experienced at the Bahrain Grand Prix.
The Finnish driver started on pole position but was unable to open up a gap due to his tyre pressures being too high in the opening stint.
He lost the lead to Sebastian Vettel through the first pitstop phase and Bottas later slipped behind his team-mate Lewis Hamilton, who was on an alternative strategy.
Hamilton eventually finished second, ahead of Bottas, but a five-second time penalty for holding up Daniel Ricciardo at the pit entry prevented him from properly challenging Vettel.
“It was another reminder that we need to get everything right in order to deliver,” said Mercedes motorsport boss, Wolff.
“Ultimately, this was a day of marginal losses which cost us the win – however, as we saw particularly with Lewis, the pace was there in the car at the times when we were able to extract it.
“Our first loss came on the grid when a generator failure left Valtteri with too high starting pressures; that limited his pace in the opening stint, meaning we could not open a gap to the field and, with Lewis running behind Vettel, our strategic choices were pretty limited.
“We were on the back foot and then Ferrari played the undercut perfectly to come out ahead. We got lucky with the safety car which gave us an opportunity to recover but a problem with the wheel guns meant we lost time and positions with both cars.
“With the cars running different tyre compounds, we had to make the tough unpopular call for Valtteri to let Lewis pass; it's not something we like to do but, when the moment comes that the race win is in danger, we will always do what we need to in order to get it.
“After that, we offset Lewis' strategy as much as possible to give him the chance of closing down Sebastian in the final laps, but after he had served the five-second penalty, it left him with too much to do.”
Mercedes slipped to second in the Constructors' championship, three points behind Ferrari.
