Jenson Button has de-facto 'number 1' status at McLaren this year.
That is the view of F1 experts and former drivers Martin Brundle and Sir Jackie Stewart, despite team boss Martin Whitmarsh's claim that Sergio Perez will enjoy full equality at the British team as he replaces Lewis Hamilton from 2013.
"That is the mentality in our team," the McLaren chief told British broadcaster Sky. "They will have equal treatment. I think that competition in the team is good."
But F1 legend and triple world champion Stewart said: "It's not a question of equal footing this year.
"You've someone in Jenson who knows the business and who has been there, seen it and done it," he is quoted by the Daily Express. "He has to see himself as number 1."
Former McLaren driver turned top television commentator Brundle agrees: "With Lewis' departure, Jenson takes the lead of the team.
"He can now concentrate on that role and I think he will grow into it," he is quoted by Speed Week.