Hamilton checks out his F1 competition in Barcelona pit lane walk

Lewis Hamilton has been getting a close look at his competition ahead of the new Formula 1 season, on the day that testing began in Spain.

The seven-time World Champion will return to the track this afternoon, testing Mercedes' new W13 at Circuit de Barcelona-Catalunya.

It will be the first time the Briton has sat behind the wheel of an F1 car, other than a brief filming event at Silverstone, since he missed out on an eighth crown in Abu Dhabi last year.

He will share the track with rival Max Verstappen, who with a last-lap pass stole the title away from him back in December.

Hamilton goes on a tour of the F1 pit lane

Hamilton's new teammate, George Russell, was on morning duties for the silver arrows, putting in the laps as his Brackley-based team look to discover as much as they can about their new machine.

But while Russell focused on driving, Hamilton went for a stroll through the pit lane to assess the new cars of his championship rivals, hidden under a hood, sunglasses and a face mask.

The 37-year-old took his time to watch Verstappen take his seat as Red Bull fired up their new RB18, before taking a walk down the pit lane to look inside every garage.

Mercedes not discounting any teams from F1 title fight

Hamilton's glances into the garages included 2021 backmarker teams Haas, Alfa Romeo and Williams.

It comes after Mercedes boss Toto Wolff made clear that he is not prepared to rule any of Mercedes' competitors out for the F1 title this season, with the sport's regulation change, perhaps the biggest in history, expected to throw up some surprises.

"I'm not discounting any teams," Wolff said, speaking to members of the media that included RacingNews365.com.

"Everyone could be high up in the standings at the beginning of the season, because we've seen it in 2009 with the double diffuser.

"If a team has innovated and discovered opportunities that could be game changers, everyone can be ahead at the beginning."