The FIA has ruled out asking Formula 1's top teams to run a third car this season, despite growing doubts about grid numbers at the end of the 2014 campaign.
With Caterham battling to get its cars to the United States Grand Prix, and uncertainty about Marussia's plans after it ran a sole entry in Russia, there is a chance there could be fewer than 20 cars on the grid in the final three races.
If grid numbers fall below 20 then clauses in the commercial arrangements between teams, the FIA and Formula One Management mean that some outfits could be asked to run an extra car.
But with agreements believed to state the teams will get 60-days' notice to run a third car, and clarification about the livery, driver qualification and points-scoring capability of an extra machine still needed, such a move has been ruled out for now.
High level sources have confirmed that, for the remainder of 2014, the FIA will not seek replacement cars on the grid to bolster numbers up to 20 in the event that entries fall.
DOUBTS OVER 2015 PLAN
Even if the door would be theoretically open for third cars in 2015, bigger teams are still not convinced it is a realistic proposition.
Mercedes motorsport boss Toto Wolff said recently that he thinks it could not happen without a very long lead time.
"It is reflected in the regulations that if the grid falls below 20 cars, the FIA and the rights holder may ask a team to supply a third car," said Wolff about the latest situation regarding third cars. "Now, that is quite a call.
"First of all, you need to set up and do the logistics, the infrastructure and the resources to run a third car.
"Then you need intelligent rules around who runs a third car. Where is it being run? Who drives it? Is it going to score points? And which livery will it be running?
"There is so much to be sorted out before we can run it and I don't see it happening.
"I knock on wood as I hope that all teams will stay in F1. But if the past history has shown that teams come and go, then this is not something that would be a great shock."