Mercedes kept an incredibly low profile in week one of pre-season testing, with neither 5-time F1 World Champion Lewis Hamilton nor Valtteri Bottas setting a headline time.

And it was to be expected, with the reigning world champion – regardless of era – generally waiting until the last minute to show its hand… if at all.

But, there’s a lot on the line this year, with Mercedes able to equal Ferrari as the most dominant constructor of all time: six consecutive world titles unrivalled, two ahead of McLaren and Red Bull Racing.

And it’s a record that Mercedes’ head of motorsport Toto Wolff is refusing to publically target yet, with new aero regulations this year.

“I think that you can't say that we are aiming for a sixth title [double], because that would be ignoring the fact that there's a massive [aero] change of regulation, the points go back to zero and the five doubles that we have scored make us tremendously proud, but [they] give us no guarantee or no sense of entitlement for this sixth potential title, insofar I think that we just need to push flat-out, as if it would be any other season and then see whether it's good enough.”

The Silver Arrows have seen off this type of challenge before, as the first team to remain dominant through sweeping technical regulation changes – as demonstrated from 2016 to 2017.

And with 2019’s versions likely to retain the status quo at the front of the grid, it’s now down to whether Ferrari can retain its momentum – in again challenging Mercedes for outright control.

"So Lewis [Hamilton] is the absolute favourite again because he has been driving incredibly lately and his team does an incredible job, so I think the odds are in his favour. Then Sebastian [Vettel] is the obvious challenger, but I would also, if I was a betting man, I would put some on [Charles] Leclerc and [Max] Verstappen because I think both of them can be a big, big surprise this year in an exciting way.”

Hamilton, one of just seven winners in the hybrid era, is in the form of his life, though – with 51 wins from the 100 races since 2014. Vettel is in third, behind Nico Rosberg. Daniel Ricciardo is fourth with seven.

And the Brit is on a roll for a sixth world title, just one away from the great Michael Schumacher’s total.

So it’ll be all eyes on Mercedes in this last week of pre-season testing, as the Silver Arrows finally turn up the wick in preparation for qualifying at Round 1 in Melbourne, Australia.