Valtteri Bottas has described the Canadian GP race weekend as a personal "wake-up call".
With his new beard on show after a lacklustre 2018, the Finnish driver came out of the box with surprisingly strong form early in 2019.
But more recently, his championship lead has become a 29-point deficit to Mercedes teammate Lewis Hamilton.
Mika Salo, a former F1 driver, said Bottas' performance was particularly "strange" in Canada.
Bottas said his Montreal weekend started to go wrong in qualifying, with a messy lap meaning he qualified just sixth. He finished the race fourth.
"I was really confident but I made some mistakes in Q3 and that cost me quite a lot of points," Bottas is quoted by Iltalehti newspaper.
"I can be happy with fourth as I made a couple of places and got the extra point for the fastest lap. But I can't really afford weekends like that if I want to fight for the championship."
Another former Finnish F1 driver, JJ Lehto, says all is not lost for Bottas.
"The battle is definitely going on, but in normal circumstances it will now take quite a lot of races for him to catch up," he said.
"Nowadays, reliability is so high that you can't count on failures for the others."
Bottas was quoted by the Dutch publication Formule 1 as admitting Canada was even a "a bit of a wake-up call that I can definitely learn from".
His title hopes aside, that is also true given that Esteban Ocon is waiting in the wings and hoping for Bottas' race seat for 2020.
Bottas insisted: "There is no pressure. I'm happy with how things have been going this year.
"Ok, I made a mistake in qualifying because maybe I wanted too much, but that can happen. I don't think this was due to pressure."