Max Verstappen called for sharper work and a faster car from his Red Bull team on Saturday after qualifying second behind Mercedes' George Russell for the Canadian Grand Prix.
The series leader and three-time world champion who won last year's race from pole said rival teams had caught Red Bull this year and they needed to react now.
He has been beaten in two of the last three races and seen his aura of invincibility eroded, said AFP.
He said he was unfazed by being beaten by Russell even though they had identical lap times because the Briton clocked his time first.
“No, I’m not worried by that," Verstappen said.
"And probably I should be pleasantly surprised to be on the front row in a way, but we lacked pace.
"The time Mercedes did in FP3 – that is not possible for us. Not really. And we have had a messy weekend. We need to tidy up and we need to improve our car too.
"There will be more rain tomorrow and then it will be all about how the tyres hold up in the race – and whoever is best at that wins.
"So we have got a lot of work to do and it is not the easiest circuit for us here. But our target has to be that we are good everywhere."
His team-mate Sergio Perez, who signed an extended contract a week earlier, said qualifying had been a 'disaster' as he failed to progress beyond Q1 for the second successive race.
"It was a total disaster as I just couldn't get the grip," Perez said. "The issue was mainly the rear end of the car, the rear axle. It felt a lot worse and I couldn’t get the tyres switched on."
Perez qualified 16th and faces a scrap on Sunday if he is to score any points for the team.
