Pit-lane starts for all four drivers from Haas and Aston Martin have now been confirmed ahead of the United States Grand Prix.
Due to changes in the specification of parts and set-up changes to their cars, Kevin Magnussen, Nico Hulkenberg, Lance Stroll and Fernando Alonso will line up at the end of the pits, leaving 16 cars on the grid.
Both teams have brought sizeable upgrade packages to the Circuit of the Americas, but with limited practice time available on the Sprint weekend, have struggled to gain understanding and knowledge of the new parts with parc fermé conditions kicking in after just 60 minutes of practice on Friday before qualifying.
Under the long-standing rules, any major set-up changes or changes of components to those of a different specification trigger a pit-lane start.
Magnussen and Hulkenberg both have a different specification of rear wing assembly fitted to their VF-23 machines from those which entered parc fermé on Friday.
As for Stroll and Alonso, Aston Martin has taken a different approach and intends to use the race as an extended test session.
Alonso is set to revert to the Qatar specification of floor to enable a back-to-back evaluation with Stroll's upgraded spec triggering a pit-lane start for the two-time World Champion.
As for Stroll, he has taken a new set-up on his AMR23, meaning he joins his team-mate and the Haas drivers.