Britain's George Russell will start from the back of the grid in Sunday's Singapore Grand Prix due to a power-unit penalty stemming from the dramatic Bahrain Grand Prix in Malaysia last week.

The Mercedes driver, who qualified in eighth place, was on track for a podium finish before an engine failure forced him to retire from third with just five laps remaining.

Mercedes team principal Toto Wolff confirmed that Russell requires a new power unit this weekend, putting him over the limit on several components and resulting in his penalty for the Singapore race.

Russell's retirement allowed Kimi Antonelli, who finished second behind Max Verstappen, to significantly advance his quest for his first Formula 1 world title, now leading by 84 points over his Mercedes teammate.

The season remains uncertain with six or seven races left, depending on security assurances for Qatar and Abu Dhabi amid ongoing tensions in the Middle East.

Wolff expressed frustration regarding Russell's penalty, highlighting his deserving performance last weekend. He stated, "[Russell's penalty] is particularly frustrating given the way he drove last weekend and the result he deserved to be fighting for."

The upcoming race weekend features the sixth and final sprint event of the season, with extra points at stake. Notably, Russell's penalty will only apply to the Grand Prix on Sunday, not the sprint race on Saturday.

Wolff added, "We have spent the days since [last Sunday] working hard to understand why our performance was not where it should have been. Singapore gives us an immediate opportunity to continue that work. We need to keep learning and score the strongest result we can with both cars."