Eddie Irvine's championship bid misfired again yesterday as Ferrari sank without trace in free practice ahead of tomorrow's Italian Grand Prix at Monza.

The good luck that rained down on the Irishman in Austria and Germany has been evaporating slowly in recent weeks and after a disastrously uncompetitive Belgian Grand Prix saw Irvine's world championship lead erased, it looked like Ferrari dreams of a first driver's title in 20 years were being eradicated with it.

However, after an impressive test in Monza last week, with Irvine among the quickest, the drought appeared to be ending and the omens once more looked good. But yesterday Irvine plunged to 16th, one place above his team-mate Mika Salo in free practice.

"When we came here for the test last week, the first couple of days the car was really bad," Irvine said after the afternoon session.

"Then we changed something and three laps later I set a time that was quicker than anybody else in the three days. So we started this weekend with the set-up from the last day of testing which we thought was the right set-up. But the car is not performing the way it did and I can't understand why. We have to look at it. If we get the car performing the way it did in the last day of that test I'd be very, very happy."

Irvine will take heart, though, from an out of sorts performance by the McLarens of Mika Hakkinen and David Coulthard. Fifth and eighth at the end of the afternoon session, although world championship leader Hakkinen remained unconcerned.

"The set-up always changes here and that's what we were working on," he said.

While Ferrari and McLaren tinkered, Williams appeared to get thing right straight away. With Ralf Schumacher quickest and team-mate Alessandro Zanardi third, Jordan may yet have to put off any early moves to celebrate third place in the constructor's championship with the installation of new signing Jarno Trulli for Damon Hill in the season's closing two races. However, while the Jordans struggled, with Heinz-Harald Frentzen's track time restricted by an off and Damon Hill finishing 10th, Williams technical director Patrick Head was refusing to crow over his charges times. "It's a good result but it is only Friday," he said.

Frentzen, despite his 13th place yesterday, was unconcerned about the team's haphazard day. "It was frustrating to lose so much of the session but we have done a lot of testing in Monza so it shouldn't affect us too much in terms of how we perform in qualifying.