Williams has conceded that it appears to have a problem in qualifying with its new, Cosworth-powered FW33, as for the second race weekend in swift succession in F1 2011, the car's pace evaporated just when it really mattered, leaving Rubens Barrichello and Pastor Maldonado with much work to do in the Malaysian Grand Prix.

After winding up eleventh (Maldonado) and twelfth (Barrichello) at the close of play on Friday, the Williams duo slipped back to 14th and 16th respectively in FP3 and then, in the qualifying session itself, just 15th and 18th, with the Brazilian veteran turning the tables on his young rookie team-mate.

Regardless of which one of the pair out-qualified the other, however, the fact remains that like in Melbourne a fortnight ago, Williams significantly underperformed in qualifying at Sepang, leaving its two drivers with a mountain to climb on Sunday.

"We don't seem to have the pace we need in qualifying," reflected Barrichello. "We were stronger in Melbourne, so we need to analyse why and see where we are in the race. All things considered, my lap was okay - in fact, it was probably one of my best laps around Malaysia - but it wasn't good enough to counteract the performance of the car today. Whether we get rain or a steady run in a dry race, though, we'll be going for points."

"That was a difficult session, and we definitely didn't expect to be out in Q1," concurred Maldonado after missing the cut by just over a tenth of a second, ironically being edged out by his own team-mate. "The car wasn't feeling as good as it was this morning. I had a bit of traffic as well, so I didn't get a clean lap.

"We have a lot of tyres now for tomorrow, and the car goes better on long runs than it does in qualifying. With a good strategy, who knows what will happen? There's no reason why we can't get into the points."

The Grove-based outfit's technical director Sam Michael admitted that he was frustrated to see the FW33's competitive edge suddenly and unexpectedly disappear - but the softly-spoken Australian stresses that in a grand prix that frequently turns into a weather-dictated lottery, anything remains possible.

"That certainly wasn't the qualifying session we were aiming for," he acknowledged, "but we struggled to get more out of the FW33 today. Tomorrow's race will be interesting, whether that's due to potentially wet weather or the number of pit-stops made in the dry. Our focus is to score points."