F1: The five most likely

NOBODY'S going to challenge Lewis and Nico. That’s the accepted wisdom in the paddock after every technical director who wasn’t called Paddy Lowe clicked shut their laptops after the Barcelona pre-season tests and had a moment of quiet reflection.

The Mercedes-AMG Petronas steamroller appears unstoppable.

That said, there are precedents here. Fernando Alonso was an unbackable favourite in 2007, only for Kimi Räikkönen to relegate the Spaniard to third in the final race. So who has the potential to cause some long faces in Brackley this time round?

There are a few worth watching but momentum and unpredictability make a driver's prospects more interesting than most at the start of the season.

Forget about old stagers like Button, Massa and Räikkönen. Experienced hands in the same teams are unlikely to reverse last season's fortunes, sadly. So for all their service to the sport, and the love the sport has for them, they are not drivers to watch.

And while there's novelty value in seeing a 17 year-old race in F1 (Max Verstappen) and watching the in-car footage to see if Carlos Sainz's son (Carlos Sainz Jr) can match his Dad's blurry hand-speed, drivers so new and so far back are unlikely to seriously challenge at the pointy end of the season.

Pastor Maldonado? He’s one to watch, if only to see who he’s going to spear into the scenery.

For momentum, Daniel Ricciardo has to be the man most likely to challenge them again, energised by his three wins last season.

That would have been good in any season, but it was sensational in a year when another team was so dominant: nobody else outside Mercedes won.

He smiles and laughs and looks like he's actually enjoying being an F1 driver, and that ease counts for more than you might think.

And he just set the fastest time for an F1 driver on Top Gear, so it's all settled. The only thing that could be an issue is that this is the second season after his breakout year. Expectations are higher.

Speaking of momentum, his team-mate Daniil Kvyat's move to the top of the Red Bull ladder after just one season will have swollen his confidence and indicates abilities that Christian Horner can see on his monitors, but that perhaps aren't obvious to us through the noise of other influences.

He’ll be looking to put one over on the crowd favourite in Albert Park.

Valtteri Bottas might just be the season’s dark horse. Fourth last year, the Williams-Mercedes package looks even stronger for this campaign and momentum certainly appears to be with the Finn, who claimed six podiums.

With 38 races under his belt, the Finn’s excised the rookie rashness from his racecraft and now looks the finished article; quick, assured and decisive.

It feels obvious to nominate multiple world champions, but as vast talents in new teams, Sebastian Vettel and Fernando Alonso fit our unpredictability requirement.

It's crazy to think that Alonso won his first championship a decade ago: he is unquestionably still capable of winning another, and his race-craft makes him the driver the others most fear arriving in their mirrors.

Add to his unpredictability the fact that he's back at an old team with unhappy memories, and driving a car with a new - and rather good - engine supplier. He’ll miss Melbourne, and huge question marks still hang over both his Barcelona incident and the durability of the McLaren-Honda package, but a driver as good as Alonso just can’t be overlooked.

Neither he nor Vettel has much momentum after a zero-win season, but both will be highly motivated to at least destroy their team-mates and prove they still have it.

Vettel may have timed his move to Ferrari well: that team cannot afford to stay dismal for long, and a colossal shake-out at Maranello might give him the car a four-time world champion deserves.

If there’s one thing that’s defined Vettel’s career to date, it’s a certain guile to put himself in the right seat at the right time. Does he know something we don’t? We’ll know a few more answers come Sunday.