Fernando Alonso might be regarded as a de-facto "reserve driver" at McLaren this year.
That is the news from team boss Zak Brown, even though earlier speculation that the newly-retired Alonso might drive the 2019 car in winter testing was wide of the mark.
"Fernando is still part of the team with our Indy 500 project," Brown insisted to Europa Press at the launch of McLaren's new orange and blue car.
"I think it's likely that we will not announce a reserve driver, but I think there are drivers who, if we need someone at short notice, could play that role."
It is believed Brown was not referring to official test driver Sergio Sette Camara, who is linked to McLaren sponsor Petrobras. The F2 driver does not have a super license.
Sette Camara confirmed that he will focus on Formula 2 this year.
"For me, this is my most important programme," he told Brazil's Globo. "In my opinion, it is this (F2) that will dictate my future, not so much my work as test driver."
Boss Brown said the newly launched 2019 car is the start of McLaren's return after years of disappointing results.
"We are rebuilding and it will take time," he is quoted by AS newspaper.
"Andreas Seidl is joining the project (on May 1) at the front of the team, and James Key will be our technical director," Brown added.