Maverick Vinales admits he can see his MotoGP title ambitions "slipping away" following a dismal run to 14th place in qualifying at Motegi.
Yamaha rider Vinales lies third in the standings, 28 points down on leader Marc Marquez with four rounds left, and needs a big result in Japan to keep his championship challenge intact.
However, after struggling in the wet during Friday practice, Vinales' fortunes failed to improve on Saturday and he missed out on an automatic Q2 spot in third practice.
He was then only fourth in Q1, leaving him down on the fifth row of the grid - his worst qualifying result since he qualified in the same position at Misano in 2015.
"We tried everything," said Vinales. "Honestly, nothing helps and it is just the same problem during all the year, the traction.
"I do my best, I cannot do anything more with the bike we have right now.
"For sure it is a shame, because we are trying to win the title. But like this it is impossible, I can't do anything in the rain.
"Whatever I do, riding smooth, riding aggressively, braking late, very early, the problem is the same one, the traction.
"Every time I go out on track, and I see myself in 10th position, I see the title slipping away, especially because my rivals are in the first positions."
Asked what he can hope to achieve from such a lowly grid slot on Sunday, the Spaniard replied: "What I can do is give my best as always, make my job and hope for better weather."
With Valentino Rossi's slick tyre gamble failing to pay off in Q2, satellite Tech 3 rider Johann Zarco was easily the best of the Yamahas in qualifying, taking a surprise second career pole.
Vinales said he had no idea how Zarco could be so competitive on a year-old machine, and said he would try not to dwell on the subject.
"If it's strange for you, imagine [how it is] for me," he said when asked what he made of the Frenchman's performance. "I don't know.
"It's better to think nothing [about it], trying to make your work and take the best result."