Kamui Kobayashi believes a place in the top six on the Melbourne grid would have been achievable had he been able to save some new soft tyres for Q3.
The Sauber driver used the best of his rubber reaching the final part of qualifying, but still took ninth on the grid.
"Overall performance wise we are not too bad and now we see what we have done in the winter was okay," he said. "Of course there are still things to improve, but this is only the first grand prix and making it into Q3 is good. I want to thank the team.
"I only wish I had a set of new tyres left for Q3, instead of the used set of soft tyres, as then I think P6 would have been possible. However, I believe today is positive news and I'm very happy to give that to Japan."
His team-mate Sergio Perez took 13th on the grid for his first Formula 1 race, despite a complicated qualifying day.
"My first qualifying started quite well with P6 in Q1, and this was mainly because in the third free practice I couldn't run on soft tyres and low fuel as we lost a lot of time due to a hydraulic problem," he said.
"In Q2 we were a bit tight on time after the yellow flag, and then on my last flying lap I had traffic in the final sector and could not get the most out of the tyres.
"Today a better result was possible, and this is a shame. But generally I feel very comfortable and hope for a good race tomorrow with some points at the end."
Team boss Peter Sauber said Perez's form on his debut had been particularly pleasing.
"From Kamui we knew what he could do, but Sergio, our rookie, was a nice surprise," he said.