Sebastian Vettel believes pre-season favourites Ferrari have worked out why they lacked pace in Formula One’s Australian opener but he stopped short on Thursday of promising a resurgence in Bahrain.

The German and new team mate Charles Leclerc were surprisingly slow around Melbourne’s Albert Park circuit two weeks ago, finishing fourth and fifth nearly a minute behind the Mercedes of race winner Valtteri Bottas.

That prompted much head-scratching back at the team’s Maranello headquarters, especially after Ferrari had lit up the timing screens in winter testing.

"The last couple of weeks have been very intense," Vettel told reporters at Bahrain’s Sakhir desert track.

"I think we have some answers but, as always, you never get all the answers because we never get the chance to go back and repeat.

"I think we are not in a position to be able to make promises. The truth is that we need to wait and see."

Ferrari have the best record of any team in Bahrain with six wins. Vettel, the most successful driver there, has won four times including the last two in a row.

Ferrari also arrived in Bahrain last year with questions about their pace but Vettel led a front-row lockout in qualifying, followed by a win. He also seized pole position at the next two races.

The German is hopeful Ferrari’s performance this year in Melbourne, with Albert Park regarded as an outlier circuit, will again be a one-off.

"There's always some lessons -- some were about the set-up, others were about the (circuit) configuration,” said the four-times world champion.

"You throw everything in the mix and we have reason to believe we should be stronger here, but I don't want to put a number to it."

Leclerc echoed those comments.

"We expect to be more competitive," said the Monegasque. "We will only see here whether it was only track specific or if there is something else, but I am pretty confident in the package we have."