Lando Norris could qualify only third for the sprint race at the Qatar Grand Prix on the weekend the McLaren driver could clinch the world title for the first time.
Norris' team-mate Oscar Piastri, one of his two championship rivals, took pole, with Mercedes' George Russell second.
AdvertisementAdvertisementAdvertisementRed Bull's Max Verstappen, the other driver in title contention and tied on points 24 behind Norris, had a difficult session and will line up sixth for the sprint.
Norris cannot win the title after the sprint on Saturday, but can in the grand prix on Sunday if he can gain two points on both Piastri and Verstappen.
Piastri had a smooth qualifying for the sprint, fastest on both his flying laps.
Norris, just hundredths behind Piastri on his first lap, ran wide out of the final corner on his second lap and was pipped by Russell.
Piastri, who has seen Norris make up 50 points on him since he won the Dutch Grand Prix at the end of August said: "It's been a good day, which is nice for a change.
AdvertisementAdvertisementAdvertisement"The car has felt good all day. We made some good adjustments into qualifying. The pace was there all day."
Piastri's pole came despite a major overseer moment on the entry to Turn Four, which he estimated had cost him about 0.2secs and he described as "pretty scary - turning left in a right-hand corner is never good, especially when you're doing however many hundreds of kilometres an hour you're doing there".
There are eight points for a win in the sprint, seven for second and so on down to eighth place.
Although overshadowed by the title fight, arguably the star of sprint qualifying was Fernando Alonso, who put the Aston Martin fourth on the grid, an outstanding performance for a team that lies eighth in the constructors' championship.
AdvertisementAdvertisementAdvertisementAnd underlying Verstappen's troubles, the Dutchman was beaten by his team-mate Yuki Tsunoda in qualifying for the first time this season, the Japanese faster by 0.009secs.
It may transpire that Verstappen's car was handicapped when he set his fastest time.
He ran off track at the exit of Turn Four on his first attempt, bouncing across the gravel trap violently, the sort of incident in which an F1 car's floor can incur damage.
He was also complaining, with added swear words, through the session over the radio about the car bouncing.
Behind him, Mercedes' Kimi Antonelli was seventh, with the Williams of Carlos Sainz and Alex Albon sandwiching Leclerc.
More to follow