After setting the fastest times in second and third practice, Alonso was in the hunt for pole position in Bahrain but ran early to set his final Q3 lap and duly qualified in fifth.
The Aston Martin driver ran 0.628s adrift of polesitter Max Verstappen to also fall behind Sergio Perez and an all-Ferrari second row. But the two-time champion kept both Mercedes at arms’ length, with Russell clocking sixth ahead of his team-mate Lewis Hamilton.
However, Russell believes Ferrari has already shown its hand as its race pace is often worse than its qualifying speed, meaning Alonso will be the one to watch in the GP.
Asked by Autosport if Mercedes could leapfrog Ferrari in the race, Russell instead cited the Spaniard: “Their race pace is always a little bit worse than their qualifying pace.
“Us is the opposite. So, qualifying three tenths behind [Ferrari] when they’ve probably been the fastest car in a single lap, I think we’re in a good place to fight for that P3.
“But to be honest, Fernando is probably more of a dark horse than Ferrari.”
The Briton did add that fifth on the grid for Alonso and eighth for the injured Lance Stroll was lower than he might have predicted, based on the Aston AMR23’s strong practice showing.
Russell continued: “I was expecting a little bit more from them, to be honest.
“I was a little bit surprised we were so close to them for all the pace they showed. I guess it was a good session for us.
“It’s interesting how they were so competitive in practice but ultimately qualifying is the first time you truly get a real read.
“I would say, going into this weekend, this is roughly where we expected to be.”
Mercedes gains five-times better than planned
Russell added that set-up tweaks Mercedes made to its W14 overnight proved five times more effective than initially predicted.
While he held back on what the precise changes were, Russell reckoned they had saved half a second after he and Hamilton were only on the fringes of the top 10 in Friday practice.
However, the team could not bank on them being permanent fixes since they were yet to fully understand why they had been so transformative.
Russell said: “The change we made, we expected to find probably a tenth.
“We found maybe five or six tenths. We need to understand why that is.
“Obviously, that is positive news, but we need to understand it.
“After FP3, we didn’t really focus on understanding it. We just focused on maximising performance. So, that’s going to be a job for Monday.”
