Osterman could lead the United States to their fourth straight gold
The United States beat Japan and Canada on the same day to extend their Olympic winning streak to 18 matches.
The Americans beat Japan 7-0 before resuming their suspended game with Canada from Thursday trailing 1-0.
However, Cat Osterman pitched four no-hit innings for the US as her side came back to win 8-1.
Also on Friday, Canada beat China 1-0, a victory that all but assured them a spot in next week's medal round. Australia defeated Chinese Taipei 3-1.
Venezuela recorded their first Olympic softball win, 8-0 over the Netherlands, in a game called after five innings.
In four games, the Americans have posted three shutouts, outscored the opposition 29-1 and allowed just two hits in 24 innings.