The German automaker had entered the Paul Ricard weekend as one of the contenders for a race win, with the ultra-smooth circuit believed to be perfectly suited to its W13.
But Hamilton and team-mate George Russell couldn’t come close to the pace of the leading cars Ferrari and Red Bull, as they finished fourth and fifth fastest in the second session.
With Russell seven tenths behind Carlos Sainz and Hamilton two tenths behind, the pair admitted things hadn’t gone as well as they had hoped.
Hamilton said: “We have a lot of work to do, a long way to go yet.
The car is not spectacular here and we don’t know why. But I hope that overnight we can take a small step forward. So I hope that will be the case tomorrow.
The seven-time champion felt Mercedes were paying the price for a downforce deficit rather than being held back by one of the porpoising issues that marred his form earlier in the campaign.
Lewis Hamilton, Mercedes W13
Photo by: Alastair Staley / Motorsport Images
When asked where the car was missing, Hamilton replied, “Just everywhere. It’s just every corner.
“I will have to dig deeper into the data. But I feel like we lack support today. But otherwise, it’s fine.
“I mean, I can only have empathy for guys who are even further back.
“I think in general this generation of cars is definitely nowhere near as good as it was in terms of grips and things that we had in the past. But it’s also the first year of this generation.
“I’m sure it will get better over the years. But yes, we have work to do. We are a little later than expected this weekend.
Russell felt Mercedes were better in the race than at one-lap pace, but said the team could not afford to have poor qualifying and fall into the midfield peloton if they wanted a realistic chance of getting on the podium.
“I think our high fuel pace was probably better than our low fuel pace so we need to make sure we optimize tomorrow to make sure there are no mid-pack cars between us and the four first,” he said.
“But I think the Ferrari is probably stronger than us, and I think Max looks very quick as usual. So work to do.
While expectations were high at the start of the weekend for potential, Russell felt the team were far from favorites to secure a win.
“Outside shooting is probably the way to put it,” he said.
“We’re probably a bit off the pace today than we would have hoped. Work to do tonight and back to the factories. But never say never.