Toro Rosso heads into the 2014 Formula 1 season opener still 'one month' behind schedule, according to team boss Franz Tost.
After switching from Ferrari to Renault power for 2014, the team has endured a difficult pre-season dominated by recurring reliability and performance concerns.
It will therefore enter the Australian Grand Prix having completed less than half the mileage of early favourite Mercedes.
Tost admits the team is not fully ready for the season to commence, but says there is no sense of despondency about the situation, particularly given the encouraging progress the team made over the final two days in Bahrain.
"So far, we're in line with maybe the race starting one month too early," Tost said.
"I would like to have another two, three weeks' time to test, but nevertheless that is how it is scheduled.
"We have to make the best out of it.
"We improved the performance, especially [over] the last two days [in Bahrain pre-season], so we are [heading] in a good way."
While Tost admitted the team still has outstanding performance work, he said the need to improve reliability will take absolute precedence in the early stages of the season.
"The first, and decisive, factor will be to see the chequered flag," he explained.
"So our main topic is to improve reliability.
"We will see [after] where we are from the performance [side].
"From the technical side we still have to sort out some issues with the power unit but Renault is aware of this; I accept that it's part of the new process.
"Let's wait for the first race to see where we really are.
"They [Renault] are professional enough and have enough experience to sort out any weak points. I'm convinced about this."