Toto Wolff believes the vast performance swings between Lewis Hamilton and George Russell is "difficult to comprehend", but hinted at the Pirelli tyres as a factor.
In the Abu Dhabi Grand Prix weekend, Hamilton was unable to extract performance from the W14, qualifying 11th and finishing ninth while Russell enjoyed a cleaner, smoother event.
He qualified fourth and bagged just a second podium of the season in third, having comfortably had about three-tenths in performance over the five-time Yas Marina winner throughout.
Such big performance swings have been common over the season, with the trend not just limited to Mercedes, but as Wolff pointed out, Ferrari, McLaren and even Red Bull.
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Wolff questions tyres
"It is just difficult to comprehend that good drivers in various teams have these oscillations in performance," Wolff told media including RacingNews365.
"You've seen it this weekend with [Carlos] Sainz and [Charles] Leclerc, you've seen it with George and Lewis and Oscar [Piastri] and Lando [Norris], and the obvious one is [Sergio] Perez and [Max] Verstappen.
"Perez is not a second slower than Max, so what [is causing it?]
"We have seen it swinging in both directions, and fundamentally, I think all around it is the tyre grip.
"If you are able to kind of have it in a sweet spot, a stable flat platform that you start to work with at the beginning of the weekend, then you can extract performance.
"If you are not there, there's just no performance, you're falling off the cliff, literally.
"I have no explanation for it, and the only one this year who understood how to drive these tyres is Max."