Sebastian Vettel says he doesn't know where Red Bull sit in the F1 pecking order going into the opening round of the 2013 season in Australia later this month.

The defending champions have topped the times just once so far after Mark Webber let the way on the first day of the final session in Barcelona, although many feel the RB9 will still be the car to beat when the field arrives in Melbourne for the opening race of the year.

Speaking following his penultimate day of running in Barcelona on Friday, Vettel said he was unsure of exactly where the defending champions sit compared to their rivals even if others are talking up the potential of the Milton Keynes-based squad.

"It's not that we believe that we will go to Melbourne and blitz everybody," he was quoted by the official F1 website. "Fact is that we don't know where we are. We certainly do have a rough idea - and that leaves us with a quite good feeling. We are happy with the balance and the way the car behaves - and that is a very positive signal - but whether that is enough or not we do not know at this stage, so I would say that there is still work to do.

"In fairness we have conditions here in Barcelona that we will definitely not see in Melbourne and there is always the chance that somebody deals with the Melbourne conditions better than the rest.

"To be honest I had very little time to look at how others are doing, so I am impressed by how much we've been under scrutiny from others. I think Melbourne will show the trend - but I doubt that we will be able to establish any real pecking order based on one or two races. Last year we also had to learn that it takes much longer these days to know who is hot and who is not."

The German did however admit that he feels Red Bull is in a better position now with the new car than it was twelve months ago with the RB8.

"Overall I would say that right now we have a better starting point than we had last year," he reflected, "and that doesn't sound too bad, does it?"