Mercedes Team Principal Toto Wolff conceded his squad endured a “bruising day” after a difficult outing in the São Paulo Grand Prix Sprint.
George Russell and Lewis Hamilton started from fourth and fifth respectively with the former showcasing strong pace early on.
The Briton briefly moved ahead of McLaren's Lando Norris for second place but later dropped back behind his compatriot before being shuffled back by Red Bull's Sergio Perez.
Hamilton suffered a more challenging outing as he was seen battling the rear end of his car throughout the 24 laps and was overtaken by Charles Leclerc's Ferrari and AlphaTauri's Yuki Tsunoda.
Mercedes' performance contrasted greatly with 12 months ago in Brazil, where it prevailed in both the Sprint and the Grand Prix.
“I think we had a little bit too weak of a rear end,” Wolff told Sky Sports.
“And then obviously it's balancing them on the knife's edge. Trying to hold onto the pace is maybe something we need to learn for tomorrow, but a bruising day.”
Viewed by others:
Wolff asserts there are no quick fixes
Hamilton beefed up Mercedes' chances ahead of the weekend around the Interlagos Circuit and asserted he would be ready to compete if it was within reaching distance of Red Bull.
However, the seven-time World Champion crossed the line 34 seconds down on race-winner Verstappen in a 24-lap race.
Asked if there were any quick fixes to implement overnight, Wolff replied: “I don't think there is, I don't think there is a magic screw you can turn and then everything is fixed.
“It was very odd. Everything went against us today. We need to really scratch our head hard for what we can do tomorrow and improve.”