Valtteri Bottas kicked off his career with Mercedes with a solid drive in Melbourne and a third place podium finish.
The Finn took some time however to find his pace in the first stint, not entirely satisfied with the handling of his W08 on the ultra-soft compound.
Shod with the soft rubber after his tyre change the Finn appeared to reel in team mate Lewis Hamilton as the Mercedes men still hoped to challenge Vettel up front.
But ultimately the gap between the Silver Arrows stabilised.
"I was expecting a little bit better, but it was a decent start," he acknowledged.
"I think the main question mark for me was the first stint. I just didn't have the pace I should have had really.
"The car was sliding a lot around with the ultra-soft tyre. But once we put the soft towards the end it was feeling very good and very consistent.
"I really pushed the car and enjoyed driving it that way, the pace was good."
Bottas began to make inroads into Hamilton's advantage but just could not completely bridge the gap, underling the difficulties of following another car under the new-spec rules.
"I was trying to get close but the problem is, once you get within a couple of seconds, you just lose so much grip in the corners, definitely more than we'd lose before which is a shame.
"It's going to be very difficult in some places to battle with other cars.
Despite the decent start to the season, Bottas admits that Ferrari's level of performance is impressive but cannot go unchecked.
"I think it's going to be a big challenge, we're going to have to work really hard if we want to beat them," said the Finn.
"They were quicker today no doubt, so we need to improve plenty of things. I'm glad there are 19 races to go and this team is definitely not standing still.
"I'm happy even though I'm third, even if it's not the best result, but I know there's a lot more to come."
GALLERY: all the pics from Sunday's action
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