Lewis Hamilton’s F1 championship hopes have been dealt another significant blow after it was confirmed he will serve a grid penalty for the Brazilian Grand Prix.
Hamilton will be demoted five places for Sunday’s race at Interlagos after Mercedes changed his engine for the fifth time this season.
The British driver, who trails Max Verstappen by 19 points, will take the potentially title-damaging punishment following the conclusion of Saturday's sprint race.
It means even if he wins the shortened race on Saturday, he will start Sunday’s main event no higher than sixth.
Qualifying for the sprint takes place at 4pm local time (7pm Irish time) on Friday.
Mercedes believe taking the punishment here will at least allow Hamilton to compete for points in the sprint race – the third and concluding event of the season.
The winner of Saturday’s race takes three points, the runner-up two points, and third place, one point. The result also determines the grid for the grand prix on Sunday.
Hamilton’s latest setback comes just five days after title rival Verstappen drove to a comprehensive win in Mexico City to extend his championship lead.
The Mercedes driver enters the final four rounds having failed to win the championship when trailing with fewer than six races remaining.
But seven-times champion Hamilton, sporting a one-off helmet in tribute to his childhood hero – the Brazilian triple world champion Ayrton Senna – will be able to take some comfort from topping the time charts in the opening practice session of the weekend.
He finished 0.367 seconds clear of rival Verstappen, with Red Bull team-mate Sergio Perez four tenths back in third. Valtteri Bottas took fourth in the other Mercedes.
Elsewhere, Pierre Gasly finished fifth for AlphaTauri with Ferrari's Carlos Sainz and Charles Leclerc sixth and seventh respectively, but British driver Lando Norris was only 15th in his McLaren.
Despite the threat of bad weather, practice played out in dry conditions. However, rain is forecast to disrupt qualifying.