Lewis Hamilton has described Mercedes' problems as "much, much bigger" than previous seasons as the competitive action for the 2022 F1 campaign got underway.
Hamilton ended the first day of running at the Bahrain International Circuit in ninth position, more than a second off the pace set by Max Verstappen in the Red Bull.
With TV footage showing Hamilton and teammate George Russell continuing to battle porpoising, the seven-time World Champion admitted plenty of work still lies ahead.
"We've had small problems in the past, relatively, compared to this year, [but] we're faced with much, much bigger problems this year," said Hamilton, who also encountered brake and DRS issues in FP2.
"Everything we do to try and kind of fix [things], doesn't really change [the situation], so it appears that it's probably going to be more of longer-term fix – nothing in the short-term."
Mercedes under threat from AlphaTauri, Alfa Romeo
Russell feels that Mercedes could end up being dragged into a midfield battle with the likes of AlphaTauri and Alfa Romeo at this weekend's season opener, putting early pace-setters Red Bull and Ferrari out of his mind.
While Russell fared slightly better than Hamilton over a single lap, finishing half a second away from Verstappen in fourth place, he pointed to being "consistently over a second slower than our rivals" on the longer runs.
"I think it's clear. It's all about lap time and we're certainly not where we want to be," Russell commented.
"I think we've made a bit of progress solving some issues, but the pace is not there at all at the moment, so we need to really go over the data tonight to understand.
"We're both struggling with the car and we're a long way off the pace of Red Bull, Ferrari, even the likes of AlphaTauri, Alfa Romeo, who are seemingly on our pace or even quicker, so we've got a bit of work to do."
A weekend of damage limitation?
Echoing Hamilton's comments, Russell sees no quick fix to the issues Mercedes are experiencing.
"I mean, it's always evolving, but there's nothing drastic we can do overnight," he added.
"You can't suddenly chop things up or turn the car upside down, because that would just be pretty reckless.
"We need to go away and analyse the stuff. We've still got a race weekend on our hands and we still need to make the best of this situation. Maybe [it will be] damage limitation, but we need to look into it."
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