Ferrari driver Sebastian Vettel insists his team have "made a step", but is unsure just how much they have improved.
The German four-time world champion officially joined the famous Italy-based team in November last year after a successful spell at Red Bull.
The 16-time constructors' champions have endured several lean seasons, with the last of their titles coming in 2008.
Ferrari are considered among a group of teams behind Mercedes when it comes to pace heading into the 2015 season, and Vettel said there had definitely been improvement.
But the 27-year-old appeared to hint that Ferrari would need some luck, or for Mercedes to make a mistake.
"We've made a step. We're yet to find out how big that step is. And then it depends," Vettel told a media conference in Melbourne on Thursday.
"We've seen last year, there are chances to win races - not just for Mercedes.
"If you put yourself in a very strong position, probably at the beginning of the season right behind, if something happens you're there. It's not what they want, but these things can happen to all of the drivers, all of the teams."
Vettel, whose future was a constant talking point throughout 2014 before he announced his Ferrari move, seemed more than comfortable in red.
He said their targets were to once again be Formula One's best.
"I think there is a lot of history in the team and obviously for me it's an honour to race for Ferrari. I'm very happy at this stage," Vettel said.
"I can't wait to get in the car and finally start racing with the team.
"Equally, we know that we have to work hard because our ambition is very high and we want to make sure Ferrari gets back to the top."