Mercedes have admitted Lewis Hamilton is considering taking an engine penalty for this weekend's Turkish GP that would see him start at the back of the grid.
World championship leader Hamilton has raced with three engines so far this season, which is the maximum permitted in F1 rules.
If he uses a fourth he would have to start at the back of the grid, just as title rival Max Verstappen did last time out at the Russian GP when he roared back from 20th to finish second.
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Mercedes boss Toto Wolff says Mercedes are considering taking the hit in Istanbul in an attempt to avoid reliability issues in the final seven races of a tightly-contested season.
"It's a possibility. When, and how, is not yet decided,” Wolff told Sky Sports.
"Most important is that you don't DNF [Did Not Finish] because of a reliability issue. You can cope with swings, whether you finish second, third, I think that is OK, the championship is going to go long. But if you don't finish...
“So we are looking at the parameters of the engines, making sure we don't suffer from any reliability problems."
Verstappen’s impressive performance in Russia means he is only two points behind Hamilton in the championship standings.
Hamilton won in Turkey in 2020 to clinch his seventh world title and will be hoping for a repeat on Sunday.
"Lewis has been tremendous there,” added Wolff. “But we have to take each race at a time. It's so difficult, the cars are so close. I'm curious to see how this championship evolves."
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