Lewis Hamilton says that his debut season at Mercedes is unpredictable amid changes in performance expectations surrounding the British driver.

Hamilton swapped proven winners McLaren for the Silver Arrows in the off-season, a move which prompted many to predict that the 28-year-old would suffer, with the latter team only registering a solitary victory since returning to the sport in 2010.

However, these attitudes have changed after the 2008 world champion and teammate Nico Rosberg topped the timesheets on the final weekend of testing at Barcelona to dramatically cut the odds on a victory in Melbourne.

"First people were talking us down and saying we were going to do terrible and now all of a sudden they've changed their opinions," Hamilton told Sky Sports News. "People are all over the place!"

"I don't think anyone knows what is going to happen. I think what we have to make people remember is that this team and this car have struggled for the last couple of years and that doesn't change with a click of the fingers.

"We have to keep working, but we've done a good job over the winter, and I'm really proud of the team and grateful to have been part of that journey."

The season gets underway with the Australian Grand Prix on Sunday.