Sauber's drivers have put a brave face on swirling speculation about the future of the Swiss team.

Before the 2016 season even starts in Melbourne this weekend, it emerged not only that Sauber paid its staff late for February, but that technical boss Mark Smith has suddenly left the team.

Nonetheless, drivers Felipe Nasr and Marcus Ericsson kicked off their stay in Melbourne this week with a trip to the local zoo, posing with kangaroos for the international media.

"It was fun. They are really nice and calm," Nasr, referring to the wildlife, is quoted as saying by German news agency DPA.

Less calm are the rumours about Sauber's future and finances, but Swede Ericsson insisted: "I have to focus only on the racing.

"I think there will be no more problems."

Ericsson finished 2015 with nine points.