United States 5, Australia 0

A large section of merry Australian fans -- six of whom wore curly yellow and green wigs -- waved flags, shook toy kangaroos and belted out the words to the Aussie pop anthem "Down Under," even after the public address announcer at the Olympic softball stadium turned off the music. "Can't ya hear, can't ya hear that thunder," the fans roared, unconcerned about the quality of the performance.

"You better run," they concluded, "you better take cover!"

But what was intended as a song of celebration might have been better taken as a warning -- to the Australian players. Under cloudless blue skies and searing sunshine, the thunder came from the usual place, the U.S. dugout, arguably the home of the slickest, steadiest team of these Games. Seeking their third straight Olympic title, the American women won their semifinal with another run-of-the-mill trouncing, this one by a 5-0 margin.

"Every time we play the United States," Australian second baseman Fiona Crawford said, "everything seems to be going wrong."

That's bad news for Australia, which beat Japan later in the day to get one more shot at the Americans in Monday's gold medal final.

Everything has gone right for the U.S. team in these Games. In fact, the good times have been rolling for more than a year; Team USA hasn't lost since last July (78 straight games). Australia managed three hits against Lisa Fernandez on Sunday, and that qualified as an offensive explosion.

The U.S. team, which has scored 46 runs in eight games in the Olympic tournament, hasn't given up a single one. The pitching staff has allowed only 14 hits, an average of fewer than two per outing. The U.S. players seem so enthusiastic, so excited about the game, they sprint -- full speed -- on and off the field at the end of innings.

"They are playing," Australia Coach Simon Roskvist said, "beautiful softball."

Indeed, they have made the dusty diamond at the Olympic softball park their personal palette. Fernandez, one of four three-time Olympians on the roster, threatened to fracture a few wrists and dislodge a few vertebrae Sunday with her devastating change-up, which she employed with a teasing frequency. The Aussies, who hit the ball out of the infield just six times, looked as if they were poking at butterflies.

Fernandez also helped in the batter's box, breaking a scoreless tie through three innings with a run-scoring double in the fourth. Two innings later, Team USA used a walk, a hit batsman, three singles and a sacrifice fly to score three runs. The afternoon's punctuation came in the form of a smash over the right field wall by right fielder Kelly Kretschman, who at 5 feet 6 is one of the smallest players on the team.

"We're on a mission," center fielder Laura Berg, a two-time Olympian, said. "We've got something to prove."

Asked what the U.S. team could possibly have to prove, Berg looked momentarily perplexed.

"We want to dominate," she said. "That's our goal."

The United States has managed to avoid the slip-ups that slowed it in the last two Olympic softball tournaments. At the Sydney Summer Games in 2000, the U.S. team stunningly lost three games in a row after having posted a 110-game winning streak. At the 1996 Summer Games, the United States, 110-1 entering the tournament, lost once to Australia. Those blips aside, the U.S. team has been the best in the world for 18 years. It has won five straight world titles. It allowed 17 runs all of last year.

"You just can't" have a letdown, Berg said. "In the Olympic Games, you just can't, plain and simple."

The United States was quiet for three innings, going hitless against pitcher Melanie Roche until shortstop Tracey Mosley hit a slash bunt in the fourth inning, opening a door the U.S. team proceeded to plow through.

"We've just been working all year to put it all together, and you're seeing it all come together now," said pitcher Catherine Osterman of the University of Texas, one of two collegiate players on the U.S. roster.

Having swept through the Olympic tournament without a stumble, U.S. players have their eyes solidly on a third straight gold. As if to put everyone in the proper mind-set, pitcher Jennie Finch walked around the clubhouse Sunday sprinkling glitter on her teammates' hair.

"We've left no stone unturned," said first baseman Leah O'Brien-Amico, a member of the 1996 and 2000 Olympic teams. "Coach [Mike] Candrea has made sure our preparation has been so thorough. The emotions of playing and the passion for the game are what you're seeing right now."

U.S. starting pitcher Lisa Fernandez reacts after the final out in a semifinal victory over Australia, which the Americans face again today for the gold medal.Australia pitcher Melanie Roche looks toward the outfield as American Kelly Kretschman rounds the bases behind her after a sixth-inning homer.Shortstop Natasha Watley is part of a U.S. softball program that has won 78 consecutive games.