Verstappen on sprint pole after another settings issue
Red Bull's Max Verstappen beat Mercedes driver George Russell to sprint pole at the Singapore Grand Prix.
Verstappen, fresh from his and Red Bull's first victory of the season in Malaysia last weekend, was 0.12 seconds quicker than the Briton, with Ferrari's Charles Leclerc third.
McLaren's Oscar Piastri and Lando Norris were fourth and fifth ahead of Ferrari's Lewis Hamilton, who went early in final qualifying and fell down the order from initially being second behind Leclerc.
Championship leader Kimi Antonelli, using the Mercedes upgrade that underperformed in Malaysia while Russell is on the previous specification, could manage only seventh.
And there were further glitches with the engine settings provided by governing body the FIA five days after the formation laps in the wet in Malaysia saw cars reduced to crawling speed as a result of a software bug.
The settings issue, which was combined with a glitch in the F1 timing system that delayed the start of second qualifying, did not affect the order.
However, it did involve the settings being different before and after a red flag caused by a crash for Sergio Perez's Cadillac and left drivers complaining of reduced power.
It involved overtake mode - which allows an extra 0.5MJ of energy to be harvested - being switched on and off again in the space of 28 seconds.
The FIA has been approached for comment but has not yet provided an explanation.
Mercedes critics think I'm Satan - Wolff
Verstappen's pole lap appeared to be further confirmation of Red Bull's resurgence after his dominant win in Malaysia but he faces an investigation for overtaking under yellow flags shown before the first session was stopped for the Perez incident.
Russell's performance compared with that of Antonelli raises further doubts about the efficacy of the Mercedes upgrade introduced in Malaysia.
It was their biggest car update since the Canadian Grand Prix in June but team boss Toto Wolff said at Sepang that it had appeared to take them backwards rather than forwards.
Mercedes split the car spec here in Singapore in an attempt to better understand its performance but Antonelli ended the session 0.573secs behind Russell.
Antonelli, who leads the championship by 84 points going into the weekend, said: "Already FP1 I was struggling and there is still a lot to understand about this package. Really the car is very difficult, very unpredictable, very difficult to put a lap together. It's a shame. I was coming with high hopes but so far it has been very difficult.
"It's going to be a difficult weekend unless we can pull something out tomorrow. Other than that it is going very tricky. I don't really see where we can find 0.7secs but you never know."
Wolff said before sprint qualifying: "The new car seems to be a little more tricky to drive. Not saying it's necessarily slower, because there will be goodness in it, but maybe we haven't just found a way of putting it all together and tuning it. The older car is a bit more stable, grippy, but that is really just one data point."
Top 10
1. Max Verstappen (Red Bull) - 1:31.156
2. George Russell (Mercedes) +0.120
3. Charles Leclerc (Ferrari) +0.243
4. Oscar Piastri (McLaren) +0.298
5. Lando Norris (McLaren) +0.431
6. Lewis Hamilton (Ferrari) +0.546
7. Kimi Antonelli (Mercedes) +0.693
8. Liam Lawson (Racing Bulls) +1.185
9. Isack Hadjar (Red Bull) lap time deleted
10. Pierre Gasly (Alpine) lap time deleted
Singapore Grand Prix
9-11 October
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