Russell struggled with bouncing in Barcelona's high-speed corners which made his Mercedes W14 even trickier to drive on the limit, with the Briton reporting a belief that there was something wrong with his tyres early in Q1.
"The car wasn't feeling okay every single lap of the session," said Russell when asked by Motorsport.com about the car's behaviour. "We made some small changes from FP3 to quali, and the car was bouncing a lot in the high-speed corners.
"The corners that were easily flat in practice, I couldn't take flat. I couldn't get the tyres working, it kind of all went wrong. From the first lap in Q1, I knew we weren't going to be having a good day. It was strange.
"We should be capitalising on conditions like that and we usually do. As a team, we're usually very good when it's challenging, but today, especially on my side it just wasn't there."
Russell was eliminated in Q2 after making contact with team-mate Lewis Hamilton and lapping over six-tenths shy of Max Verstappen's benchmark time in that phase.
Referencing the one-and-a-half second deficit to Q1 leader Nico Hulkenberg to highlight his struggle, Russell added: "I was trying all sorts with the out-lap, all sorts with pressures. Probably just got ourselves a bit lost and confused.
"The set-up change we made into quali definitely was directionally wrong for those cold, damp, greasy conditions, which is a shame, especially because I think we have a fast race car. I think in FP2 we probably had the second-quickest car after Max, ahead of the Ferraris.
"So not all is lost. We just need to be patient tomorrow in trying to carve back through."
Mercedes team principal Toto Wolff backed Russell's bleak assessment of his weekend, conceding the team had gone the wrong way with his car.
"It was clear from the beginning that the set-up direction we went with George made the car worse," he said. "I think from the get-go he complained that he didn't feel any grip, that he had bouncing, the car understeered where before it oversteered.
"And that's something which we need to unwind now to understand exactly what we could have done differently."