Merc once again played second fiddle to Ferrari and Red Bull as Charles Leclerc was fastest in FP1 and Max Verstappen quickest in the afternoon with Hamilton only fourth fastest in FP2 and 0.798s behind the Dutchman.
The five-time World Champion had admitted in the lead-up to the Russian GP weekend that his Mercedes squad are far from favourites and he believes they are still well off the pace of the Ferraris.
“It’s been a day of discovery and exploring,” said Hamilton. “It started off not too bad and then it just didn’t really improve as with the others, who made some big progressions.
“We anticipated that we’re losing eight tenths of a second to the Ferraris or something on the straights. Nonetheless, we’ve been improving but they are improving at a serious rate.
“We’ve just been figuring out how we can improve the car, but it’s not an easy task.”
Asked if they can challenge the front two of Red Bull and Ferrari for the remainder of the weekend, he replied: “That is the million dollar question, I don’t know.
“Naturally I believe in my guys. I don’t think we’re getting the maximum maximum out of our car.
“That’s been the key issue we have had for the last three races. We’re still trying to discover it. It’s not easy out there.
“It’s good to see the competition doing well. But we want to be in there fighting.”
Team-mate Valtteri Bottas was a little bit faster than Hamilton as he was 0.646s off the leading Red Bull, but he admits they need to find something extra ahead of qualifying.
“Always good fun on this track, but Red Bull and Ferrari were a bit too quick today,” he said.
“It felt good and there were no massive balance issues with the car, maybe just struggling a little bit with the overall grip and sliding around. Apart from that, it felt good and I had fun.
“”We need to find some gains if we want to fight for the pole tomorrow.”