Australian Grand Prix: Can anyone stop the Mercedes-Hamilton juggernaut?

Four months since the chequered flag fell in Abu Dhabi, the 2018 Formula 1 season kicks off this weekend at Melbourne's iconic Albert Park, home of the Australian Grand Prix. As the locals always say: "It's a great place for a race!".

WHO'S IN CONTENTION?

Lewis Hamilton heads to Melbourne aiming to add to two previous victories in Australia and kickstart his bid for a fifth world drivers' title. A strong performance during pre-season means the 2017 champion is the favourite once again, with team-mate Valtteri Bottas full of confidence after winning the season-ending Abu Dhabi Grand Prix in November.

Hamilton may be the bookies' favourite, but Ferrari's Sebastian Vettel and Red Bull's home hope Daniel Ricciardo should also be in contention this weekend, with the latter aiming to become the first Australian to win a grand prix on home soil.

Both Ricciardo and team-mate Max Verstappen are still waiting for a first Australian Grand Prix podium (Ricciardo lost second place in 2014 through disqualification), but the RB14 looked quick in testing, appearing to at least be on par with Ferrari on long-run pace.

This street circuit contains a mix of slow to medium-speed corners, and will feature a third DRS zone this year, softening Red Bull's power deficit to Mercedes and enhancing the team's chances of a strong result.

Hamilton's biggest threat last year came from Vettel, who won in Melbourne but missed out on the title after a late-season wobble. The German set the pace during pre-season this year as both he and Kimi Raikkonen locked out the top two fastest times of the two-week test in Barcelona.

Mercedes opted not to run the fastest hypersoft tyre during testing, so we'll have to wait until Saturday's qualifying session to see how they compare on pure one-lap pace.

CAN ANYONE SPRING A SURPRISE?

Further down the grid, the midfield looks to have been shaken up a fair bit over the winter as Renault and McLaren appear to have jumped ahead of Force India and Williams, with Haas raising a few eyebrows by posting the sixth-quickest time in Barcelona.

McLaren's performance will be the focus of much scrutiny over the weekend. After three barren years with Honda, all eyes will be on the team to see if they're able to translate the potential they showed during pre-season into results, and at the same time prove any reliability concerns were little more than teething trouble.

Considering how bad the disastrous McLaren-Honda relationship was, a little 'teething trouble' seems a reasonable price to pay to start afresh with new power unit supplier Renault.

Ironically though, with the Honda engine bolted into the back of a Toro Rosso, it managed 822 laps over the two weeks of testing; significantly more than McLaren managed in any of their three pre-season tests with Honda.

Keep an eye out for Fernando Alonso's face if Pierre Gasly or Brendon Hartley manage to outqualify him on Saturday…

HALO, IS IT ME YOU'RE LOOKING FOR?

Perhaps the most discussed change over the winter is the introduction of the halo.

Sunday's race will be the first competitive appearance for the FIA's new mandatory safety device, aimed at improving cockpit protection for the drivers.

Opinion has been divided on whether its introduction was necessary, but the majority of drivers asked about it during pre-season testing were unanimous in their dislike of its 'ugly' appearance.

One team determined to find a positive from the halo's inclusion this season is McLaren, who last week raised a few smiles with the announcement that flip-flop manufacturer Gandys will be their official halo sponsor as part of a commercial tie-up in Melbourne.

And they say F1 takes itself too seriously...

OVERDOING THE OVERTAKES?

As mentioned, a third DRS zone has been added to the circuit for Sunday's race, as F1 looks to improve on a paltry return of five passing manoeuvres in last year's race.

Two of those came in one moment as Esteban Ocon and Nico Hulkenberg roared past Alonso's underpowered McLaren, while Vettel pipped pole-sitter Hamilton to victory thanks to Ferrari's greater strategy.

As well as the home straight and the run between turns two and three, DRS will also be enabled between turns 12 and 13.

F1 said of the move: "If they fail to make a move stick there, it is hoped they will be closer into the next activation zone that follows the final two corners of the 16-turn circuit."