Pirelli's 2012 season got underway with the new Cinturato Green intermediate tyre - named after the range with which Pirelli started its original Formula One campaign in the 1950s - as Toro Rosso's new recruit Jules Vergne took to a damp track in Albert Park for the first free practice session of the year.

Teams are allocated a total of 11 sets of slick tyres for the race weekend, and under this year's rules they now have every set available to them from the start of free practice. However, rain dominated proceedings during both of Friday's sessions in Australia and the rules also state that if both Friday sessions are wet, one set of dry tyres can be carried over to the following day. Furthermore, if either of the two free practice sessions is wet, the teams are entitled to an extra set of intermediate tyres, above their usual allocation of four sets of intermediates and three sets of wets per race weekend.

In the first free practice session, which started in damp conditions but progressively dried out, McLaren driver Jenson Button went quickest thanks to a time of 1:27.560 on the P Zero White medium compound. This turned out to be the fastest time of the day, during which the medium and soft slicks, as well as both wet weather tyres, were used at various points.

Rain continued in the afternoon and with drier conditions predicted for the rest of the weekend, there was comparatively little running at the start of the second session while it stayed wet. All teams started on the full wet tyres, with Ferrari's Fernando Alonso becoming the first driver to head out on intermediates with an hour to go. After the track finally dried out again with less than half an hour remaining, Michael Schumacher clinched the fastest time of the session for Mercedes on the P Zero White medium tyre in the final seconds: 1:29.183.

Most of the installation and set-up laps were done on intermediate and wet tyres in view of the conditions, with very few long runs carried out on the soft tyres in particular. Overall, the changing conditions made it hard to draw many firm conclusions.

Paul Hembery: "With a very wide variety of mixed conditions today, we got to run all four types of tyre that we have brought here, and the teams were able to carry out some important work to establish crossover points. The weather is expected to remain dry for the rest of the weekend, so it's understandable that most drivers chose to concentrate on dry running. But because there was so little dry track time, we will not see a completely accurate picture of relative performance emerge until tomorrow. We noted that the medium tyre was particularly well suited to the conditions today, and that the performance gap between the two compounds has significantly decreased but we've got plenty of data to analyse tonight before we can come up with any detailed times."

Numbers of the day:

Sets used overall:

Soft: 12
Medium: 37
Intermediates: 24
Wet: 18

Highest number of laps per compound:

Soft: 11
Medium: 15
Intermediate: 12
Wet: 8

Check out our Friday gallery, here.