Dr Helmut Marko says he is confident Daniel Ricciardo will stay at Red Bull in 2019.
The Australian driver is currently delaying his decision, amid rumours he might switch to Mercedes, Ferrari or even McLaren.
'Where would he go'
But Marko, the Red Bull consultant, thinks those moves are all unlikely.
READ: Ricciardo not denying $20m McLaren offer
"Where would he go? To Mercedes? When all you hear is Hamilton praise Bottas?
Or Ferrari? Where Vettel praises Kimi Raikkonen and Ferrari praises Leclerc? I think neither team is interested in Ricciardo," he told Bild am Sonntag newspaper.
Marko tipped Ricciardo to eventually sign a new Red Bull deal because it is the team that gives the 28-year-old the best chance of winning.
Ricciardo not short of options
"He certainly cannot do that at McLaren, even if they made him an outrageous offer.
And he is allowed to drive freely with us rather than be the number 2 at Mercedes or Ferrari. For example, if Raikkonen was free at Ferrari, things would be different for him," said the Austrian.
But Marko said that even if Ricciardo does leave, Red Bull could cope with the loss.
"We have alternatives, and we are bound by deadlines. In the autumn, a decision must be made.
We would love to continue with Daniel, but it has to be right for both sides," he said.