Sergio Perez and Valtteri Bottas will start today's Australian Grand Prix from the pit lane, after changes were made to both drivers' cars under parc ferme conditions.
Perez was due to start from 20th and last position, after a torrid Qualifying session in which he failed to set a representative lap time after sliding into the gravel at Turn 3.
With little to lose in terms of track position, Red Bull have elected to fit a third control electronics unit and energy store for the season to Perez’s RB19.
Drivers are only permitted to use two of these components during the season without facing sanctions, meaning Perez is condemned to a pit lane start.
Alfa Romeo's Bottas will join Perez in the pit lane after his team made overnight changes to his suspension that contravened parc ferme regulations.
Bottas had been due to line up alongside Perez on the back row after qualifying 19th, meaning the Finn also has little to lose by starting from the pit lane.