BEIJING— On a hot, hazy morning, the U.S. softball team sweated like never before.

This seemingly unbeatable team that produced one rout after another as if off an assembly line was pushed to the edge Wednesday — a 4-1 victory over Japan that went to extra innings.

The Americans scored four runs in the ninth, with Crystl Bustos hitting a three-run homer. The victory extended the Americans' Olympic winning streak to 22 in a sport that won't be back for the 2012 London Games and whose future is uncertain.

Now, the U.S. (8-0) is one victory shy of a fourth consecutive gold medal, and Japan could be back for that one Thursday. The Japanese were to play Australia later Wednesday, with the winner meeting the Americans and the loser getting bronze.

The score was tied after seven innings, forcing the international tiebreaker in the eighth in which teams begin their at-bats with a runner at second.

Despite having first base open, Japan pitched to Bustos. Softball's most fearsome hitter responded with her fifth homer of these games, nearly sending the ball out of the stadium.Monica Abbott pitched eight shutout innings for the U.S. Behind Abbott, the U.S. team had beaten Japan 7-0 in round-robin play. That game was one of five shortened games by the Americans in the preliminaries.

At beach volleyball, U.S. men Todd Rogers and Phil Dalhausser earned a trip to the gold-medal match by beating a duo from Georgia. They'll play a Brazilian tandem on Friday. Also, BMX cycling made its Olympic debut, with all four Americans advancing. Mike Day won the time trial in each of his heats, while Kyle Bennett dislocated his left shoulder but is expected to be OK.

A day earlier, Americans got another glimpse on the podium of gymnasts Shawn Johnson and Nastia Liukin and an introduction to freestyle gold medalist wrestler Henry Cejudo.

The son of illegal immigrants from Mexico, Cejudo was 4 when he last saw his dad. His mom raised six kids and often struggled to make ends meet. The family moved more times than anyone remembers.

He became a national champ at 17, then defied conventional wisdom by blowing off college to study nothing but wrestling. Now he's the world's best in the 55-kilogram division, the youngest American ever to win an Olympic wrestling gold medal.

"Anybody can do it," he said. "It's just a matter of seeing it, believing it and just working at it, and achieving it."

Cejudo's gold and Johnson and Liukin finishing 1-2 in the balance beam were among the highlights for the U.S. delegation at the Olympics on Tuesday.