Mario Theissen says BMW Sauber have decided to delay any decisions regarding their driver line-up for the 2009 season.
"We have delayed our decisions," Theissen said at Spa. "Originally we wanted to announce next year's line-up in August but we have delayed the decision.
"It is not about being the first to announce, it is about doing the right thing."
The German squad have only Robert Kubica confirmed for next year, while the future of Nick Heidfeld is still up in the air.
Most teams with vacant seats are waiting for two-time champion Fernando Alonso to make a move before they finalise their line-ups for next year.
Heidfeld, however, said on Saturday that he was "pretty confident" he has done enough to secure a new deal with the Hinwil-based squad.
The German driver qualified in strong fifth position for the Belgian Grand Prix and Theissen reckons he proved he is back on form.
"It was a strong performance from Nick," Theissen added. "I didn't really trust the situation (in Saturday's practice, where Heidfeld was fastest) because I didn't know what the others did, but then in qualifying he was strong again with empty tanks, especially in Q2, very good. Q1 was good as well, we went out only once and then with fuel on board we have to wait and see when the other cars pit.
"You can see that he has been back on form. He is quite confident here, he likes the track and he likes difficult conditions so I hope it will be what we see in the coming weeks as well.
"Apparently most of the time at Monza he had to focus on the new aero package, he had the chance to try a few things. HE said to me that he has found some areas where he can improve in terms of tyre warm-up and it looks like it works."