Sauber reckons it will need both of its cars scoring points if it is going to have a realistic chance of catching Mercedes in the constructors' championship.
The two teams have been separated by 20 points since the Japanese Grand Prix, and neither outfit has scored again since then.
Sauber team principal Monisha Kaltenborn admits her team is particularly frustrated about its failure to capitalise on its opportunities.
"We are very disappointed," she told AUTOSPORT about the latest non-points scoring race. "We know that we have to now really make points at the remaining races to be in a position to fight ahead and also defend ourselves actually.
"So coming out with zero points is very disappointing. The target is still the same though, as we want to get up there. But it will get more difficult and tighter.
"We said a while ago we wanted to achieve all we can to try for a higher position, and it is only on the basis if you score with both cars.
"It is now very clear that we need to score with both cars, as [otherwise] we will not be able to attack."
Kaltenborn says she takes no heart from the fact that Mercedes is enduring a difficult time at the moment, having failed to score any points since the Singapore GP.
"They are still 20 points ahead of us, so they don't need to score points if we don't score," she said.
"It is about us going and scoring points. But I think it is still open."