Timo Glock fears that Virgin has not improved enough to join the established midfield runners at the start of the season.
The team was optimistic that it would be able to fight for Q2 places and start scoring points in its second year in the sport, but Glock doubts this will be possible with the package Virgin will take to Melbourne.
"At the moment, looking at the tests, that will be difficult in the first couple of races," he told Reuters. "I think we will have to wait for the bigger upgrade which comes to Turkey, where everyone will bring an update."
The German, who missed the final preseason test at Barcelona following appendix surgery, feels the main problem is that last year's midfield squads have raised the bar with their winter improvements.
"As far as I see it at the tests, we are still away from the midfield teams and Q2 will be difficult," Glock said. "Especially Toro Rosso picked up quite a lot of speed over the winter and they look very strong. Sauber as well. They were all the teams where I thought we could catch up a bit more but they made quite a big step and we still have to make a big one. It looks like we are a bit behind the target at the moment."