Red Bull team boss Christian Horner has confirmed that a DRS issue cost Max Verstappen his final Q3 run during qualifying for the Spanish Grand Prix.
Verstappen led the way from Ferrari driver Leclerc after the first Q3 runs, with his championship rival suffering a spin in the final sector.
However, the pair swapped places on the final attempts, as Leclerc delivered a storming lap and Verstappen reported a loss of power over the radio.
Horner has since explained that Verstappen encountered a problem opening the DRS, forcing him to abandon the effort.
"It wasn't actually power in the end, it was the DRS that didn't open," Horner confirmed to Sky Sports F1.
"Obviously we need to get the car back to understand what's caused that, because it opened on the back straight just as a check as he came back into the pits."
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Horner doubts Red Bull had enough for pole
Despite Verstappen's issue, Horner thinks Ferrari simply had too much pace over Ferrari in qualifying trim in Barcelona.
"I don't think we had enough today to beat that lap of Charles," he admitted.
"[It was] a great lap by him under pressure at the end there, but I'm still pleased with the front row start."
As for the race, Horner pointed to Ferrari's apparent long-run improvements in final practice and stressed the importance of tyre management in the Spanish heat.
"Charles has carried a new set of the Soft tyres into the race tomorrow, so that's strategically quite interesting," he added.
"In these temperatures, it's all going to be about tyre degradation and tyre management, so it's going to be a fascinating race."
Sergio Perez placed fifth in the other Red Bull, sandwiched by Mercedes pair George Russell and Lewis Hamilton.
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