The first deluge of the tournament gave Ivanisevic 48 minutes to rid himself of negative thoughts. When play resumed, he was transformed, swiftly gaining the confidence to turn the match in his favour, 2-6 6-4 6-4, advancing to meet Andre Agassi, the holder, in today's final.
Ivanisevic, who has never won a title in the United States, has displayed the strength of character in his matches against Sampras and Michael Chang here to suggest that Agassi could be in for a hectic afternoon.
It will be Ivanisevic's seventh ATP Tour final of the year, a run of consistency which has brought titles in Sydney, Zagreb, Dubai and Rotterdam. His concern is that he will have the stamina to give his best in today's match, which is the best of five sets.
Sampras, whose defeat means that the Austrian Thomas Muster will continue his uncomfortable reign as the world No 1, blamed himself rather than the downpour for Ivanisevic's recovery on Friday night.
"For the first set, he wasn't really in the match," the Wimbledon champion said. "He just kind of hung around, and I started pressing a little bit, missed a couple of shots, and, before I knew it, it was one set all.''
It was the first set conceded in the event by Sampras, who had beaten Ivanisevic in their last five matches, two of them at Wimbledon (last year's semi-final and the 1994 final). Gradually, the notion of Sampras playing Agassi for the Lipton title for a third year in a row evaporated.
Ivanisevic, who went into the match mistakenly believing that he would be able to hold serve with ease and could therefore concentrate on breaking his opponent, began to take greater care with his deliveries.
Moments after the rain delay, he saved himself from slipping 0-2 down in the second set by producing his first ace, a 129mph screamer. He then salvaged three break points in the sixth game, two of them with aces.
With both players regularly hitting serves of more 120mph - and frequently returning them - it was surprising how many fascinating rallies developed. Ivanisevic took control after breaking for 4-3 and saving two break points in the following game.
Steffi Graf won the women's singles title for a record fifth time - and for the third consecutive year - with a 6-1 6-3 victory over the American Chanda Rubin, who appears to have an unnerving effect on all the leading players with the exception of the Wimbledon champion.
It was the fourth time that Rubin has lost to Graf in straight sets, and so far she has been unable to extend the German beyond four games. The 20-year-old committed 26 unforced errors, five of them double faults, during the 54 minutes play, though at times Graf's pace was as blistering as the heat, which touched 120F.