2016 Formula 1 champion Nico Rosberg has branded Williams's 2026 performance a "shocker" and argued that team principal James Vowles faces a major challenge to bring the Grove outfit back to where it needs to be.
Williams entered the 2026 season already on the back foot, having missed the private testing in Barcelona in January and arrived at pre-season testing in Bahrain with an overweight car.
While it introduced major upgrades at the Miami Grand Prix, Williams has struggled to fight for points in its 2026 campaign. It currently sits ninth in the constructors' standings with 11 points - six earned by Carlos Sainz and five earned by Alex Albon.
Speaking on the Sky Sports F1 Show, Rosberg identified an overly ambitious winter development programme and the severely overweight chassis as the root causes of the team's troubles.
"Williams just messed up the winter. They messed up the winter developing this new car. They tried to be very ambitious in the way they were building the chassis, tried to go new ways, really innovate," the former Mercedes driver explained.
"It ended up backfiring, and they've got a lot too much weight on the car. And remember that 10kg of extra weight in this sport is three tenths of a second per lap. So, it's enormous if you're overweight. It's just enormous lap time lost.
"So they're fighting an uphill battle to try and recover from that because they do have the best engine. Remember, they have a Mercedes engine, so there's no excuse there. I'm sure the aerodynamics must also not be in the best place. So, they still need to make a lot of progress there."
He added: "Unfortunately, because they were in such a great place in recent years, they were really making progress, and we really thought they were moving towards the top six or top eight again permanently, and now they've dropped back massively, which is a bit of a shocker.
"It's a tough moment also for James Vowles, who I rate so highly, but he's really got to fight through this struggle now and turn things around and bring the team back towards a positive direction, which is not easy."
