McLaren driver Jenson Button has admitted that it is unclear which teams will be fastest when the season starts with the Australian Grand Prix next weekend.

However, Button hopes that McLaren's winter testing will come together so that he and new teammate Sergio Perez can impress in the first race.

"This year, I don't think any team really knows or understands the competitive order," BBC Sport quotes Button as saying. "It's been an extremely hard-to-read winter but that's part of the game.

"One of the most fascinating things about Formula 1 is the way it resets itself each and every winter. I've seen every side of that. You can have a terrible winter of testing, then turn up at the first race and be competitive.

"Equally, you can look impressive in winter testing and be nowhere in Melbourne. If you're lucky, it all comes together in the tests and you hit the ground running at the first race. That's always the goal."

The current reigning champion is Red Bull Racing's Sebastian Vettel.