Russell stressed that getting the tyres to work effectively in the face of changing track temperatures was the biggest challenge faced by all drivers, and he conceded that his team “got it wrong.”
Mercedes had a difficult Friday, with Lewis Hamilton finishing FP2 in seventh, and Russell in 10th.
Both drivers believed that there was scope for improvement on Saturday, but despite making some positive changes to their cars overnight they finished qualifying in sixth and eighth respectively.
"We definitely did,” said Russell when asked by Motorsport.com if the team made progress. “But it was just a totally up and down day.
“In FP3, we were the quickest at points, and showed really strong pace. Went out in Q1 with no grip, off the pace. Q2, the car felt back to normal, and we were quick. And we went out in Q3, and the same happened again.
“I think probably Daniel [Ricciardo] was the only driver today who was the most consistent. The Ferraris were off the pace at points. And then obviously Alex [Albon] was the quickest at points, obviously he should have been in Q3, but wasn't. It's pretty frustrating when it's like this."
Russell said that the Pirelli tyres were on a knife-edge in terms of optimisation.
"It's just how the tyre interacts with the out lap,” he said. “The temperature dropping, you're always trying to find that extra bit of performance.
“But for whatever reason, there seemed to be a sudden drop when you were a small margin over that limit.
“Either the guys just found that limit and got massive performance, or they were over the limit, and had no performance. It is a bit frustrating when it's like this, but we need to recognise we didn't get it right."
Russell acknowledged that it won’t be an easy race for Merecdes on Sunday, with managing temperatures in traffic likely to be a big challenge.
"In FP3 we thought we were fighting for the front two rows in qualifying,” he said. “And probably had a race car that was quick enough to fight for the podium.
“Starting in P8 and P6 for Lewis and I, we're going to have a really challenging day tomorrow. It's a shame.
“It's always challenging here in Mexico, everybody's fighting for brake temperatures, engine temperatures, and as soon as you're trying to overtake and fight a car, you can't, because you breach those limits.
“It's the nature of the beast, and we just need to accept we got it wrong today. And it's probably compromised our whole weekend."
Hamilton was adamant that despite the changes for qualifying the W14 was simply not quick enough.
“The car has not been great this weekend,” he said. “Story of my life at the moment this year. It's no different to any of the other races. Austin was a standout race for us, but it's back to the normal car.
“The car has generally been the same. We made a change into qualifying, I thought the car was nicer to drive at least, but in general it's just not that fast.”
Asked about his hopes for the race, Hamilton was pessimistic: “We’ve got a bit of a battle on our hands. Overheating is an issue for us. Brake overheating, these sorts of things.
“So staying in battles is going to be tough, managing tyres is going to be tough tomorrow. If we can progress forwards on strategy, then we'll try to do that.”
Additional reporting by Mandy Curi
