Buoyed by his second place in Argentina a fortnight ago, Irvine edged out his illustrious team-mate, Michael Schumacher, to head the standings in unofficial practice for tomorrow's San Marino Grand Prix here.
It may, and probably will, be very different in today's qualifying session, both Schumacher and Irvine expecting Williams-Renault to assume their familiar positions at the front of the grid. Ferrari do, however, believe they are closing on the champions and Irvine is encouraged to feel he is no longer the distant partner to the imperious German.
Schumacher sought a final flourish yesterday, smoking his tyres and jumping the kerbs in a spectacular show that had the tifosi roaring their approval, and yet he failed to dislodge the Irishman by 0.016sec, barely the head of a pint of the black stuff.
Irvine, not so long ago reviled and slammed by the Italian media as unworthy of a ride on the revered Prancing Horse, is suddenly being welcomed into the embrace of this country. He may be renowned as a playboy, but he is not seduced this time. "One day you are a god, the next a waste of space," he says.
There again, he does concede his result in Buenos Aires has had a positive effect. "It was bound to do something," he said. "The important thing is to keep the momentum going. One race won't convince anyone you are the reincarnation of Ayrton Senna.
"Getting the fastest time today is certainly better than crawling out of the back of the garage with 15th place. A win is not out of the question on Sunday, because we are in better shape than a lot of the others.
"If Williams had problems with their brakes in Melbourne then they will here. They should be better in qualifying but we appear to be pushing them in the race and if we push them here we may force them into errors."
Irvine, accused by certain fellow drivers as well as some pundits of erratic and even dangerous behaviour on the track, maintains he will be circumspect in tomorrow's race.
He said: "I'd rather walk away from here with three points from a solid fourth place than throw it off going for a second that isn't really on."
Irvine is still yearning for more testing to achieve his potential at Ferrari. "I should be doing more than I'm doing now," he said. "It's not that Michael is doing more than he should, but that I'm not doing enough."
If he does enough to earn another appearance on the podium here he will stand beneath the Union Jack, on the orders of Max Mosley, the president of FIA, motor sport's governing body. Irvine, who was accompanied by the tricolour of the Irish Republic in Argentina, said: "I wanted a neutral flag and a company has offered me one with a shamrock, but the matter has been taken out of my hands and I've been told it's got to be the Union Jack."
Schumacher says Irvine's elevation from mediocrity has come as no surprise to him. He said: "Eddie did a super job today, but we knew he was quick."
It is the influence of an Englishman, Ross Brawn, that has reinforced Schumacher's faith in the Ferrari cause. Fresh speculation that Schumacher is destined for McLaren-Mercedes next season has been dismissed by the driver's aides as "garbage".
They say Brawn, the technical director recruited from Benetton-Renault where Schumacher twice won the championship, has already instilled his order and direction within a team notorious for acting before thinking.
Doubts about Benetton's sense of direction post-Schumacher have fed speculation that their managing director, Flavio Briatore, is bound for a new career move, but Gerhard Berger and Jean Alesi steered a steady course to third and fourth places yesterday. Berger would doubtless settle for such a result to celebrate his 200th Grand Prix on a circuit that provides a poignant setting for the occasion.
The Austrian said: "I saw my first grand prix at Imola and I had my first Formula One podium finish here. I also had my worst accident here [in 1989] and this was where we had the tragedy of Roland Ratzenberger's and Ayrton's deaths in 1994. So it is emotional for me and special for me to have my 200th grand prix here."
Johnny Herbert, the British Sauber-Petronas driver, reaches his first century here. He flexed his competitive muscles with 11th position in practice. Jacques Villeneuve, the championship leader, was fifth, David Coulthard sixth and Damon Hill 13th.