Helmut Marko says Red Bull Racing is already looking for alternatives to Daniel Ricciardo for 2019, as the probability of the Aussie leaving the Milton-Keynes team grows.
Red Bull Racing's lineup will remain unchanged next season with Ricciardo and Max Verstappen, but the former has been making noises lately about a potential move in 2019.
"Verstappen has a longer contract," Marko told Auto Motor und Sport.
"But Ricciardo is already on the market. We have to look for alternatives. We will not be unprepared."
Mercedes is often cited has the Honey Badger's most likely destination should he leave Red Bull.
The energy drink company's options for 2019 could include bringing back Carlos Sainz into the family after a one-year exile to Renault.
Red Bull Racing will also likely face a change of engine suppliers in 2019 as its partnership with Renault comes to an end, with Honda perhaps its only option.
The prospect of working with the beleaguered Japanese manufacturer doesn't worry Marko however.
"Not at all. We are fully focused on the current car and 2018," said the Austrian.
"And when you look at where McLaren is now finishing, it strengthens us in the decision that we have taken at least with Toro Rosso."
In the interim, Marko insisted the team has taken measures to ensure that the troubled start it endured earlier this season is not repeated in 2018.
"There is a new procedure in the wind tunnel and we are not even finished developing this car," said the Austrian.