What happened: Mercedes' George Russell will lose five grid places for Sunday's Brazilian Grand Prix after fitting his sixth internal combustion engine of the season. Power unit problems earlier this year meant a sixth ICE was always going to be needed before the end of the year.

Why it matters: The penalty follows a Mexico City weekend in which Russell reflected on a 'tough luck' season after teammate Kimi Antonelli clinched the drivers' title. Russell started second in Mexico and finished sixth.

What to watch: Mercedes arrives in Sao Paulo 126 points clear of Ferrari in the constructors' standings, with a ninth title in reach. Russell's starting slot is set by qualifying plus the five-place drop.