Both drivers spent the morning honing aerodynamic downforce settings and engine control software for their cars prior to this afternoon's one-hour qualifying session.
In common with a number of other drivers who had hoped to put in their quickest laps during the final runs of the afternoon, Webber and Yoong lost out when red flags were displayed with minutes to go in the session following a collision between Kimi Raikkonen and Takuma Sato.
"It was a very good qualifying session for us. We had quite a frustrating morning today, but we looked hard at all the data and were able to sort the problem," Webber commented.
"We worked towards taking fuel out of the car and it was a lot better. Like everybody, we got stuck with the red flag at the end of the session. It would have been nice to have an extra run, but it's the same for everybody.
"Overall, it was a good job for our little team here at a circuit that is tough on the efficiency of everything and also that's a high-power track. Together, everybody has done a good job."
Yoong also corrected problems on his car throughout qualifying. "When we started out, the car had a lot of understeer. It got better toward the end, but then, unfortunately, due to red flags, I lost my last two timed laps," he said.
"I was on a much better lap at that point and we could undoubtedly have improved quite a lot. I wanted to show I can qualify well, and I'm just disappointed that it didn't work out today, particularly after having a good first practice session."
Team Principal Paul Stoddart added: "While the Minardi drivers line up P19 and P20 for tomorrow's Italian Grand Prix, we're reasonably content with today's performance, despite the fact neither driver was able to show his full potential in qualifying this afternoon.
"Mark's third run represented a near-perfect lap, and he was denied the chance of improving still further on his last run by heavy traffic.
"Alex's two-race break clearly has paid dividends. With his confidence restored in qualifying and driving on a track with which he is familiar, he did a good job this afternoon.
"With both cars comfortably on the grid, we now look forward to tomorrow's race."