Mercedes Team Principal Toto Wolff said the team suffered their "worst qualifying session in 10 years" in Belgium as he offered a painful conclusion over their current form.
Wolff was downbeat about where they are lacking pace over rivals Red Bull and Ferrari, particularly after George Russell put his Mercedes on pole position at the Hungaroring.
"It is, for me, the worst qualifying session I had in 10 years, irrespective of what positions we're going to start [after the grid penalties]," Wolff told media, including RacingNews365.com.
"Even being pole the previous weekend and three weeks later being nowhere is just not acceptable for ourselves."
Both Max Verstappen and Charles Leclerc are taking power unit penalties this weekend, which gave Mercedes an opportunity to capitalise with a potential win.
But Wolff believes Red Bull are in "a league of their own" this weekend.
"There's something which we totally don't understand," he said.
"Clearly Red Bull is here in a league of their own. What is the next Ferrari? Eight-tenths off? Nine-tenths off? But that is no consolation."
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Wolff: Not a positive about how the car is performing
It's been no secret that the team have struggled to pinpoint exactly where they have been losing out all weekend.
Both Russell and Lewis Hamilton complained about tyre temperatures on Friday, while Wolff's comments come after Hamilton said he won't miss this car at the end of the year.
Wolff added: "If we could understand, we could tune it, but the car is draggy on the straights; Lewis said it's 'like dragging a parachute' behind him.
"It is unstable on the rear, it understeers through Turns 8 and 9, it bounces through the high-speed [sections] and gives no confidence.
"There is not a positive that I heard about how the car performs here this weekend. I think now it's time to consolidate and decide what we do next."
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