The Briton had a frustrating time in Friday qualifying at the Azerbaijan Grand Prix as a mistake on his final Q2 run left him knocked out of the session and down in 11th on the grid.
But, without having been allowed to change car settings much because of parc ferme rules, Russell was able to put in a much more competitive performance as he grabbed a place on the second row in Saturday morning's sprint shootout qualifying session.
Reflecting on the encouraging sprint shootout pace, Russell admitted that there was some annoyance because it proved what he should have been able to do on Friday.
However, it further highlighted that Mercedes needs to get to the bottom of just why the W14 seems to only come into its element late on in the weekends and especially in Q3.
"I've mixed feelings," admitted Russell. "I'm very happy with the job in qualifying and I think P4 is exceeding our expectations. But when I got back into the pitlane I was like: bugger!
"I still made that mistake yesterday and this shows what was probably possible, but you can't always be on your A-game.
"But it's an interesting one. We always seem to get better as qualifying progresses, we always sort of come into our own come Q3 and as the weekend progresses, so there's something to learn there."
Russell said Mercedes had a few ideas about why the potential of the W14 never appears fully unlocked until Q3, but there was nothing definitive yet.
"We don't purposefully make the car in that way that it keeps seemingly getting better," he said.
"We've got some ideas why that may be but, as I said, I'm pleased that we sort of turned it around or, let's say, I improved my driving because obviously the car stays the same from yesterday."
While Russell had few complaints after the sprint shootout, team-mate Lewis Hamilton ended up sixth after losing a potential tow in his SQ3 run.
"The sessions were going really well actually," he said. "Q1 and Q2 were going well but, on my last lap, I just struggled with the rear end and I didn't get a tow at the end.
"The Red Bulls pulled too far ahead. So it was a bit unfortunate, but I gave it everything and that's all you can ever ask for."
