Oscar Piastri will start the Chinese Grand Prix on pole after edging out George Russell, whose former team-mate Lewis Hamilton won the sprint for Ferrari earlier on Saturday.
Piastri, who has never previously started a grand prix at the front of the grid but has twice topped sprint qualifying, made it two poles from two races for McLaren this season.
The Australian and his team-mate Lando Norris looked set to claim a second straight front-row lockout as several big names toiled in Q3.
But Russell split the McLarens with a lap time 0.082 seconds slower than Piastri's best, with an aborted final run from Norris opening the door for the Mercedes driver.
Norris ended up 0.152 seconds slower than Piastri, while four-time defending drivers' champion Max Verstappen was two-tenths of a second back in fourth.
Ferrari duo Hamilton and Charles Leclerc qualified in fifth and sixth respectively, while Isack Hadjar produced a brilliant drive to secure seventh for Racing Bulls.
Earlier in the day, Hamilton had sent out a statement of Ferrari's intent with a dominant victory in the first sprint race of the season.
Having secured P1 for the shortened event on Friday, Hamilton fought off a challenge from his old rival Verstappen approaching the first corner, then managed his tyres well to cruise home.
Piastri overtook a flagging Verstappen late on to take second, while Russell was fourth and Leclerc came in fifth after surrendering a place early on.
Norris dropped three places to finish eighth following an error on the opening lap, though the single point he earned keeps the Brit two ahead of Verstappen in the drivers' championship standings leading into Sunday's main race.
Qualifying top 10
1. Oscar Piastri
2. George Russell
3. Lando Norris
4. Max Verstappen
5. Lewis Hamilton
6. Charles Leclerc
7. Isack Hadjar
8. Andrea Kimi Antonelli
9. Yuki Tsunoda
10. Alex Albon
CHAMPIONSHIP STANDINGS
Drivers'
1. Lando Norris – 26
2. Max Verstappen – 24
3. George Russell – 20
Constructors'
1. McLaren – 35
2. Mercedes – 34
3. Red Bull – 24