Mercedes Team Principal Toto Wolff was unhappy with his squad's performance in qualifying for the French Grand Prix, saying "it's just not good enough".
Having failed to dip under the 1:33 mark in Q1, it looked at one point as if the Mercedes duo might have been at risk of elimination from Q2.
After switching to a brand new set of Soft tyres, Mercedes found some pace as the session wore on, with Lewis Hamilton ultimately qualifying fourth and George Russell sixth, but Wolff issued a downbeat assessment on the Silver Arrows' pace.
"I think we knew that once we got the new tyres on and we were driving the car in anger a little bit, that we're going to be there, third or fourth, like we've been all season," Wolff told Sky Sports F1.
"But yeah, it's just not good enough."
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Mercedes experimenting with set-ups
Mercedes seemed unsure of their ideal set-up for the weekend as recently as FP3, when the Silver Arrows were experimenting with different wing settings.
While Wolff acknowledged that his team had done some tinkering, he added that Mercedes were simply not quick enough to challenge the frontrunners this weekend.
"When you're a little bit on the back foot, your expectations are on a certain level for the race weekend, and if it doesn't come together, the freestyling starts," said Wolff.
"With us, it was mainly experimenting with rear wing levers and also tyre temperatures, but at the end, the overall package is just not quick enough."
Wolff also reserved praise for Hamilton, whose performance he said transcended the capabilities of the W13.
"Yeah, great job. He probably has extracted more than the car can at the moment," said Wolff of the seven-time World Champion.
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