The Mercedes Formula 1 team has no plans to give Esteban Gutierrez the 300km of running he'll need to qualify for a superlicence should he be needed as a replacement.
Along with Stoffel Vandoorne, ex-Sauber and Haas racer Gutierrez has been named as a reserve driver for the Mercedes, McLaren and Racing Point teams.
However a change to the super licence rules outlined in the FIA's International Sporting Code specifies that drivers who have not raced in F1 for three seasons have to do 300kms of running to re-qualify for a super licence.
Gutierrez last raced with Haas in 2016, while current Mercedes Formula E driver Vandoorne is eligible as he drove for McLaren in 2018.
Vandoorne is committed to FE in Berlin for the 70th Anniversary Grand Prix weekend at Silverstone, but thereafter he will be available to be the primary reserve for Mercedes.
The Brackley team has indicated that Gutierrez won't have a chance to log the necessary mileage by replacing one of its race drivers on a race weekend Friday.
It is looking for an opportunity to give him a run, potentially in its 2018 car, as used by Lewis Hamilton and Valtteri Bottas for pre-season running at Silverstone.
The sporting regulations also contain the provision for a driver who hasn't raced for two years to conduct a day of testing in a current car, but only after he has been nominated to replace a race driver, which means it is not a last-minute option.
If a driver does such a test and then doesn't race the team is docked a day of testing the following season.
Gutierrez's current ineligibility meant that when Sergio Perez tested positive for COVID-19 prior to the British GP, Racing Point had no option but to look elsewhere when it settled on Nico Hulkenberg.
"I think Esteban would have been a really strong candidate for the seat," said Mercedes team boss Toto Wolff.
"But unfortunately he didn't qualify.
"There is a new rule this year that if you haven't raced in an F1 car in an official event for the last three years, you need to have done a test of at least 300kms.
"We have to analyse now what it means for us.
"It's a shame, because giving Esteban a chance is always nice, and he's been a strong part of the team and a strong pillar of the team.
"Obviously, I don't hope that it's ever necessary that we need a reserve driver."
Both Vandoorne and Gutierrez have had seating fittings at McLaren, and driven the current car in the simulator, in case they have to be called upon.
Team principal Andreas Seidl has played down the fact that Gutierrez is not currently available.