Team USA riding momentum of D-Will's 3 into semis

BEIJING -- Deron Williams couldn't talk about the play of the night immediately after the game, because he was the Team USA player randomly selected to take a doping test afterward.

Perhaps he tested positive for that little-known substance called "gamechange-amine."

Because in a game that was a tale of two entirely different halves, what Williams did in the final four seconds of the first half played a big part in Team USA's 116-85 blowout victory over Australia.

With six seconds left in a first half in which the Australians had managed to stay within striking distance of the Americans (by using an effective zone and keeping Team USA from forcing turnovers and getting out into the open court), Mark Worthington lined up from the 3-point line and let a shot fly.

Had it gone in, it would have been a six-point game at the half. A half in which the Americans had only two assists on 21 buckets and missed 10 of their 20 free throws and 10 of their 13 3-pointers while displaying virtually none of the ferocity that had carried them into the medal round on a wave of positive vibes.

But the shot missed, and Chris Bosh corralled the rebound and made a quick outlet pass to Williams, who already had turned upcourt.

"I looked up and saw I had time to get off a shot," Williams said. "When I caught it, it was about three seconds. I thought I could make it to the basket, a big man came up and I thought I could go by him and get to the basket, but he kept backing up, and I rose up for the 3."

What was striking about the 3 was the way Williams kept his cool and was able to get his feet set right at the base of the 3-point arc. The form was perfect, and the shot was, too.

"Usually a jump shot is better [than a runner]. That's the way you practice it," Williams said.

The sequence amounted to somewhat of a six-point swing in the final six seconds, and the Americans had a 55-43 lead going into the locker room. And as we've seen over the course of these Olympics, there is little hope for anyone who falls behind by double digits against these guys, and when the Americans came out and scored the first 14 points of the second half -- Kobe Bryant scored nine of 'em -- the Australians were cooked.

G'day and g'bye.

"Plays like that, they really hurt teams," Bosh said. "Especially when the game is close, they've been playing as hard as they can and then they're down 12. It really puts them at a disadvantage and hurts their confidence. It really was a turning point."

If there's anything for the folks back home to worry about, it's whether any opponent can find a way to do what Australia did so well for 20 minutes and keep doing it for the entire 40 minutes.

What kept Team USA from having to play from behind in the first half was its work on the offensive boards, grabbing 13 of its own missed shots to create extra possessions.

Australia's game plan included dropping four players quickly back on defense while letting a fifth, one of its speedy point guards, apply ball pressure and make the Americans use an extra few precious seconds before getting their offense running. The Australians also placed a premium on protecting the ball and turned it over only once in the first quarter -- something no American opponent had managed to do until then -- and dared the U.S. team to beat them from behind the arc (the Americans did finish 12-for-25 after the poor start). And when Team USA managed to get open looks, especially from inside, the Aussies gave hard fouls and took gambles that the Americans would miss from the line.

For a half, it worked, and the game would have been even closer if Australia hadn't missed several open looks from underneath and if Andrew Bogut hadn't fumbled the ball out of bounds two times during a second quarter in which Australia coughed up seven turnovers.

"We all knew what was going on; we didn't need to talk about it much at halftime," Bosh said. "We were taking bad shots, and it just wasn't working for us. We got to playing for ourselves instead of the team."

Too much NBA style, not enough FIBA style?

"Exactly, exactly. And that doesn't really work too much unless somebody's hot," Bosh said.

Bryant said afterward that, personally, he wants to play Argentina in the semifinals because the Argentinians, as the defending Olympic champions, are the holders of exactly what the Americans want: gold medals.

"You want to be able to play the guys who won it the last time," Bryant said. "There's a sense of pride that comes with beating a champion."

Bryant's wish will come true, as Argentina defeated Greece 80-78 in a barnburner that came down to the final seconds. Manu Ginobili and friends escaped with the win when Vassilis Spanoulis missed a 3-pointer from straightaway just before the final buzzer.

So if the Americans complete their gold-medal quest, they'll have defeated three of the toughest teams in this tournament -- Greece, Spain and Argentina -- at least once apiece .

But first they have to get to the gold-medal game, in which the opponent will be either Spain or Lithuania. And if they're sharp for only 20 minutes again, winning won't be as easy against Argentina as it was against Australia.

"It's go time, and we're all ready to go. The money's on the table," Bryant said.

And, if the Americans get through Friday, the gold will be on the table Sunday.

Check out Sheridan's roundup of the quarterfinals

Chris Sheridan is an ESPN.com Insider. He has covered the U.S. senior national team since the 1996 Olympics. To e-mail Chris, click here.