Russell: Mercedes will take 'huge' confidence from Australia
The Briton will start from the front row in Melbourne on Sunday alongside dominant Red Bull champion Max Verstappen, with his teammate Lewis Hamilton third.
Their efforts, outpacing Aston Martin's Fernando Alonso and both the Ferraris, raised hopes that they could make the podium.
Team boss Toto Wolff said this week Mercedes had made "promising" progress since the first two grand prix of the season, and Russell said he couldn't be happier.
"I think we're learning more about this car, I don't think it is where we want it to be, but it's evolved, just for the set up, from Bahrain to Jeddah to here," he said.
"For sure, the tyres played a big part this weekend ... but just to be two-and-half tenths (of a second) off (Verstappen) when we have been a second on other occasions."
The result marked Mercedes' best Saturday this season, with significant upgrades in the upcoming break after Australia set to improve its W14 car further.
Russell said he was excited by the prospect.
"I think the feeling of the car is not the limitation, it feels pretty decent," he said.
"It's probably the best F1 car I have ever raced ... but we're just lacking a bit of downforce.
"But we know we have made some huge gains over the past two or three weeks and hopefully we'll be bringing that to the track sooner rather than later.
"This result today is going to give us a huge amount of confidence regardless of what tomorrow brings."
Whether their revived pace is enough to match Verstappen remains to be seen, but Russell said he was realistic.
"We have got to go for the win, obviously, but Max is going to be extremely fast, there's no hiding that," he said.
"It's difficult to overtake around this circuit so the start lap will be vital.
"But the Red Bull has extraordinary top speed so it's going to be very difficult to fight with Max, but let's see."