Felipe Nasr has admitted that Sauber's newly-launched car may not be 100% ready for the 2016 season opener in Australia in just over two weeks.
While the rest of the teams were already testing their 2016 machines last week in Barcelona, Nasr's Ferrari-powered C35 was unveiled only on Tuesday, ahead of just four days of running prior to Melbourne.
The Brazilian answered "yes" when asked if there was a financial aspect to the holdup, but added: "It was a combination of things, even involving Ferrari."
"In fact we could have brought the launch forward, but [the car] would not have been as we would have liked," he told Brazil's Globo Esporte.
"This car has a much better integration of chassis, aerodynamics and engine, and this takes time."
He added: "If I had the car a week ago we would have done much of the work that we did today. But I'd rather have the car now than to not have it.
"We have more work ahead of us, we still need time, and maybe it will not be 100% in Australia, but I am as optimistic as possible. I believe we will have a good preparation for the first race."
Nasr finished in fifth place at Melbourne last year.
