“We know that last year that we were too slow in the corners so we tried to put as much downforce as we could in the car to be as fast as possible in the corners, but now we’re paying off on the straights.
“Still in terms of overall balance, set-up, slow speed corners it is something we need to improve but that’s part of the job of this week.”
Ferrari’s showing on Thursday represented a marked improvement from their best performance of testing so far, when Vettel was sixth-fastest on day two of week one.
Ferrari have one more day of on-track testing to go before they make their way to Melbourne for the first race of the 2020 F1 campaign.
Ferrari arrived in Australia as pre-season favourites last year, but their overconfidence came to nought as Valtteri Bottas and Hamilton secured a Mercedes one-two.