Having seen off Michael Schumacher over three seasons at Mercedes, Nico Rosberg has a new challenge for 2013, but insists that partnering Lewis Hamilton is fun.

The pair are not strangers when it comes to working together, having both been nurtured by Mercedes and McLaren in their formative years, but neither would have expected the dream of racing together in the top flight to have worked out as it has.

"It is definitely very different," Rosberg noted in an interview with the official F1 website, "With Michael, it was great for me to challenge him - the legend - and to have won the internal competition in all three seasons that we were together. With Lewis it is nice to have a change.

"We were team mates in go-karts for two years, when it was the Mercedes-Benz-McLaren team. At that time we fantasised a lot, saying to each other how incredible it would be to be team mates in one of the best teams in F1. And now exactly this has happened with the Mercedes F1 team, which is really almost a fairy tale story."

Despite the obvious pleasure Rosberg derives from being reunited with his former team-mate, he knows that Hamilton brings a bigger threat than the fading Schumacher could muster.

"Sure, this pairing will also be very challenging, as Lewis is one of the best drivers out there," Rosberg admitted, "We both are extremely competitive but, on the other hand, we also get along privately very well. We can split the two sides of our lives quite well!"

Both drivers overcame tough starts to winter testing to rack up the miles and take turns at the top of the timesheets, but Rosberg isn't going to get carried away with predicting success in Melbourne.

"This winter has gone very well for us, and I think we are better prepared than ever," he conceded, "At the end of last year, we were almost one second down from the top runners, so we had to close quite a big gap. How close we really are we still have to find out, but I am very optimistic that we have made quite some progress.

"Last year, our biggest issue was the consistency, as we had quite good races at some places, but were not able to repeat this at other tracks. My impression is that this year we will see the same teams heading the grid again, - but I am very optimistic that we will also be up there and be able to show a much better performance than we did in 2012 ..... and that we will have a season that will put smiles on our faces."