Mika Salo and Pedro Diniz failed to live up to their Friday promise as they qualified 12th and 15th for the French Grand Prix.
Diniz was plagued by gearbox problems and lost momentum when he switched to the spare, which was set up for Salo.
"Things were going well for me in the first part of the session and I was 12th," said Diniz. "The latest version of the engine felt good and I was quite happy. But then I had problems with the upshifts and gradually it got to the point where I had to take to the T-car which was set-up for Mika.
"We like different things in a car, so it wasn't ideal. I lost time and momentum and can't deny I'm disappointed."
Salo struggled with Magny Cours infamous track conditions which changed dramatically in the heat.
"We were still struggling to get the set-up right each time the conditions changes," explained the Finn. "With more testing we'll get it right, but this afternoon it made life difficult.
"The good thing is that we really got my last run right, as the clouds came over and the temperature dropped. Our timing was just perfect."
Team boss Peter Sauber "We were very close to the top 10 once again but unfortunately, we did not make as big an improvement as we had expected after being fifth fastest yesterday. We arenot sure why because we had made the car better. The good thing is that we got Mika's last run just right."
Singapore / Results
Standings / After 14 races
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