So every March, as Melbourne's footy heads hang on every non-committal word from far-flung fields in the JLT Community Series, the eyes of the Formula One world turn to Barcelona, where the picturesque Circuit de Catalunya hosts two weeks of F1 testing.

Held over eight days during a two-week period, this is the first and last chance to see the teams' new cars ahead of the season opener in Melbourne. And for those locals who bother to take the 45-minute train ride from central Barcelona, followed by a 30-minute walk to the track, there's been plenty to see in the first two days of testing.

The regulation changes that have brought wider tyres, a focus on downforce aerodynamics and the promise of five-second-a-lap faster racing are starting to play out, but from the "wow" moment when the cars were unveiled last week to the first two days of testing there's been one constant - Mercedes remains the team to beat.

On day one, last year's world championship runner up Lewis Hamilton racked up 73 laps, with new teammate Valtteri Bottas posting 79. On day two, Hamilton ran a 66-lap race simulation, with Bottas knocking out 102.

Kimi Raikkonen in the improving Ferrari was fastest on day two, but only marginally and in the context of a week one test, where everyone is getting the feel of their more powerful cars. Lap times are expected to tumble by the end of next week.

All of which leaves Australia's Daniel Ricciardo with work to do after some annoying unreliability in his first session on day one.

The Red Bull driver only managed 50 laps, hampered by technical issues with a sensor and a battery. His teammate Max Verstappen had a better day two, with 89 laps and a promise of faster times for both into next week.

The drivers are expected to split up the daily driving duties for the rest of week one and having been the consistent No.2 behind Mercedes in 2016, Red Bull will be keenly watching Ferrari's improved showing over coming days

Red Bull's strength has long been its aerodynamic handling and technical chief Adrian Newey said this week that the car he's presented for testing still has some bells and whistles to come as the designers work out what extra benefits they can derive form the new regulations.

"I would say that our car is reasonably clean and simple. That is the good thing about it. At the moment I am pretty satisfied with the looks," he laughed.

"We will see some new parts coming on. But first we wanted to keep it clean and simple so we understand what we have. Maybe Mercedes has reached a higher level of maturity, but I like to start with a simple and clean car - and then you can start adding to it. If you start on a highly complicated level it is so easy to get lost."

Newey also made clear that the demands on the drivers would be greater this year, a fact shown by Ricciardo's sweaty training tweets over summer as he bulked up with his personal trainer.

"The demands on the drivers are bigger, as the cars are more physical - and, like always, some drivers will handle that better than others," Newey said.

For fans of Ricciardo, who watched his experience and racing courage edge out Verstappen's raw talent last year, this will come as a welcome relief. The West Australian at 27 looks more physically suited than 19-year-old Verstappen to the extra bulk needed to handle the added G-forces that this year's cars will produce. When Newey was asked if he'd like to have the perfect car at Barcelona, or Melbourne, Red Bull's man sounded like any AFL coach who knows where the real game will be played - and it's not the JLT Community Series or even the Circuit de Catalunya.

"That is obvious: only in Melbourne do you get points! It is there that it counts," he said, before adding an important rider. "But to do well there, you'd better start to understand your car in Barcelona."

That process has six more days to run.