Sergio Perez rued a brief but sudden lag of engine power that led to his spin in Q2 that thwarted his qualifying efforts, leaving him a lowly P13 on Sunday's Singapore Grand Prix grid.
Perez's botched session added to Red Bull's meltdown at Marina Bay, with teammate Max Verstappen also failing to make the final top-ten shootout.
Like the Dutchman, Perez was clearly unhappy with the handling and performance of his RB19 on the sweltering streets of Singapore.
While things had started off well on Friday, with Verstappen and Perez clocking in P3 and P7 at the end of FP1, the balance of Red Bull's dominant contender gradually worsened thereafter according to the Mexican.
"I had a complete disaster, I am really disappointed with the result, it was not really what we were expecting, it really hurts," Perez said.
"We made a lot of changes to the car this weekend, but nothing really worked, we need to understand it.
"We started really well with a nice balance in FP1 but then FP2 was very difficult and since then it has been tough because we have been making a few changes here and there but nothing seems to transform the balance.
"It has been tricky out there with the amount of sliding we have been doing and the balance is changing corner to corner."
Perez was on the verge of his final attempt to make Q1 when an engine glitch in Turn 2 led to him facing the wrong way, which sealed his fate. And the six-time Grand Prix winner doesn't see much hope of a turnaround in Sunday evening's race, his 250th Grand Prix start.
"In my final attempt, I had a massive under-delivery from the engine," he explained.
"Big lag, then it came back, which meant I locked [and spun] and couldn’t have a final attempt on that last lap.
"Yesterday the [race] pace looked really good, but I don’t expect great things to be honest. Given where we’re starting, it’s going to be pretty difficult to make progress from there."
Red Bull team boss Christian Horner was as perplexed as his drivers about the RB19's sudden drop in performance, insisting the team would lose no time investigating its issues.
"There’s a lot for us to consider this evening," Horner said. "First thing we need to do is put the disappointment behind us and look to work out what has caused our drop in pace and performance.
"We tried a new aero part in practice, but what we went into qualifying with is tried and tested. For whatever reason, the car just hasn’t responded at this circuit.
"There is a lot to do but we won’t give up on anything," he added.
"Starting outside of the top 10 at a track that is notoriously hard to overtake on is going to be tough but we certainly haven’t written this weekend off.
"The points are awarded on Sunday and there is plenty to play for."
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