Mercedes has debuted its 2019 challenger, the W10, with team boss Toto Wolff claiming the team started from scratch with the new car.

The team unveiled the car at Silverstone ahead of a shakedown and filming session prior to the opening pre-season test in Spain next week.

Mercedes has won both the drivers’ and constructors’ championships in each year under the current hybrid engine regulations.

Aerodynamic regulation changes have this year been fast-tracked in a bid to spice up the competition, with cars sporting simplified front wings and larger rear wings.

“The 2019 season will be a new challenge for all of us,” said Wolff.

“The regulations have changed quite substantially. We have to start from scratch, we need to prove ourselves again – against our own expectations and against our competitors.

“We start the season with zero points, so we’re taking nothing for granted and there’s absolutely no feeling of entitlement to be at the front.

“In fact, with the regulation change for the new season, every team can have a shot at the title and we’re seeing all of them as a potential threat.

“We’re eager to hit the ground running in Barcelona, to benchmark ourselves against our own simulations and see if our predictions materialise on track,” Wolff added.

“We will focus on ourselves, building up performance and hopefully be ready when the first really competitive session starts on Saturday in Melbourne.”

Hamilton last year won his fifth world championship, and fourth for Mercedes in five years, though faced a stronger challenge from Ferrari than in previous years.

The Englishman, now the second oldest on the grid behind Kimi Raikkonen, now sits second only to Michael Schumacher in the all-time wins and championships ladder.

The 34-year-old hopes his new car will see him chalk up his sixth world crown this season.

“I had a great Christmas with my family and then I went snowmobiling, I went skiing, I went surfing with Kelly Slater, which was amazing,” said Hamilton.

“I completely switched off from racing for a while, trying to focus and re-centre myself and training hard for the new season. 2018 was a great year, but I feel like 2019 can be even better.

“I want to achieve more, I want to continue to keep pushing. I feel energised and I’m ready to attack.”

Bottas is also looking forward to a strong campaign after ending the 2018 season without a win to his name.

“I’m full of energy and I’m looking forward to the new season,” Bottas said.

“I started my first training camp in early January and have been on a good path ever since.

“I did most of my training in Finland, first in the south close to my home town, then further north in Lapland because that’s where you get a proper winter.

“The conditions are quite harsh, it’s freezing cold, snow is guaranteed, but it’s a great environment to exercise and prepare your mind and your body for the upcoming fight.”

According to the team, the new W10 is a step forward in areas where its predecessor lacked, with special attention given to the suspension and aerodynamics.

Pre-season testing begins in Barcelona on Monday.