Former Formula One star David Coulthard thinks the battle for Australian Grand Prix victory is too close too call despite Mercedes having dominated winter testing.
Although Mercedes, the dominant force in 2014, has been tipped as a clear favourite for the season-opening race, Coulthard reckons the nature of the Melbourne circuit makes reading too much into testing times almost irrelevant.
"I think it's actually too close to call," Coulthard told the Australian Associated Press.
"I don't think we've seen the final 'spec' of the cars the teams will run.
"We've come off the back of Barcelona, which is a true aero circuit and you need a lot of high speed lateral stability.
"Melbourne is a different race track that requires different balance from the cars."
The Scot, a former Red Bull driver, also admitted he was very impressed by Daniel Ricciardo's performances during the past season, after dominating teammate and four-time champion Sebastian Vettel at Red Bull.
"The thing that really stood out for me is his racing ability, the wheel-to-wheel instinctive feel," Coulthard said. "That was something about him that I hadn't appreciated.
"I knew he had great speed at Toro Rosso and he was the right man to get promoted into the big team at Red Bull, but just the way he handled the adversity of a new regulation change, the difficulties of hardly doing any laps in pre-season testing, then the high of being on the podium in Melbourne before seeing it taken away.
"He really was the team leader last year and a four-time world champion in Sebastian Vettel didn't really seem to have an answer for him."