Lewis Hamilton described Mercedes' lack of pace in Belgian GP qualifying as "a real kick in the teeth" and admitted he will be glad to see the back of the team’s troublesome 2022 car.
The seven-time world champion will start fourth on the grid at Spa on Sunday due to grid penalties imposed on Red Bull's Max Verstappen, Ferrari driver Charles Leclerc and Alpine's Esteban Ocon, but could only set the seventh-fastest time in Q3.
Hamilton's best lap was almost two seconds off the quickest time clocked by Verstappen, and the Brit cut a dejected figure after finding out how far off the pace his team were.
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"Everyone is working for improvements," Hamilton said. "We came here very optimistic we could be close, but to be 1.8 seconds behind is a real kick in the teeth.
"It's a car we continue to struggle with and definitely won't miss it at the end of the year. For me, it's just focusing on how we build and design next year's car.
"The teams ahead of us are in another league and our car looked so much different today. We've got a lot of work to do, and we'll do the best we can with what we have for the rest of the season."
Russell: It's hard to comprehend | Wolff: Worst qualy in 10 years
Hamilton had put together a streak of five successive podiums before the summer break, but his hopes of earning a first victory of the season have faded throughout the weekend at Spa.
The only consolation for Hamilton was that he was able to out-qualify his team-mate George Russell, who will start a place behind Hamilton after going eighth-fastest in qualifying.
The 24-year-old had started on pole at last month's Hungarian Grand Prix before going on to take a second-consecutive podium finish, and was left struggling to process the team's struggles on the return from the summer break.
"I think I am not sure how you comprehend how you were on pole in the last race, and we are 1.8 seconds off today and not just from Max, but six tenths behind the Alpines," Russell said.
"Always when the temperature is cold, we struggle; we saw it in Imola this year, we have seen it on many other Fridays when it has been a cooler Friday, we just can't seem to get the tyres working.
"It is pretty frustrating, but I am confident we will have some more pace tomorrow compared to the Alpines and the McLarens and the Williams as well - but we will still be about half a second to a second off Red Bull and Ferrari."
Nevertheless, Russell is confident the Brackley-based outfit can achieve strong finishes in Sunday's race.
"We need to look overnight, understand it and try and be faster tomorrow," Russell said. "It is obviously not great, for sure.
"We know we are not the fastest car or the second fastest car but we definitely have a car that is capable of more than P8 and P7 so we have work to do."
Mercedes team principal Toto Wolff echoed his drivers' sentiment, and described the qualifying session as his worst for a decade.
"You can't be on pole three weeks before, albeit for very different conditions, different track, and then be 1.8 seconds off the pace at the next one," Wolff said. "So there's something which we totally don't understand, or seem to get right.
"Clearly, Red Bull is here in a league of their own, as the next Ferrari is eight tenths off. But that is no consolation.
"It's for me the worst qualifying session that I had in 10 years. And irrespective of what positions we're going to start tomorrow, being on pole the previous weekend and three weeks later being nowhere, it's just not acceptable for ourselves."
Belgian GP starting grid
1) Carlos Sainz (Ferrari)
2) Sergio Perez (Red Bull)
3) Fernando Alonso (Alpine)
4) Lewis Hamilton (Mercedes)
5) George Russell (Mercedes
6) Alex Albon (Williams)
7) Daniel Ricciardo (McLaren)
8) Pierre Gasly (Alpha Tauri)
9) Lance Stroll (Aston Martin)
10) Sebastian Vettel (Aston Martin)
11) Nicholas Latifi (Williams)
12) Kevin Magnussen (Haas)
13) Valtteri Bottas (Alfa Romeo)
14) Max Verstappen (Red Bull)
15) Charles Leclerc (Ferrari)
16) Esteban Ocon (Alpine)
17) Lando Norris (McLaren)
18) Zhou Guanyu (Alfa Romeo)
19) Mick Schumacher (Haas)
Pit Lane: Yuki Tsunoda (Alpha Tauri)