A physical battle between two undefeated teams ended in favor of Great Britain when they beat the United States 2-1 to clinch the top seed in Pool B.
Great Britain trailed by one goal in the third quarter after Michelle Vittese wound up for the long shot that flew past goalkeeper Maddie Hinch to put Team USA ahead.
Great Britain surged back late in the fourth quarter to put two goals past Jackie Briggs, who had been saving shots left and right for the U.S. all game long.
"We had a lot of possession, and just needed to turn it into a goal," Great Britain's Kate Richardson-Walsh said. "It's just believing, knowing that it would come."
On Great Britain’s fifth penalty corner, the team passed up the shot on the insert, which ultimately found its way to Sophie Bray for the tip-in. Shortly after, Alex Danson deflected a pass from outside the circle to give her team the lead with four minutes remaining in play.
This would be the first time that Team USA had ever trailed in Rio. They had a chance to tie it up on a penalty corner, but Hinch came up with a huge stop that prevented the tie.
Great Britain, the defending bronze medalists, edged the United States out of first, who needed a win or a tie to stay in the top spot.
However, for Team USA, finishing second in the pool is an accomplishment that nobody would have expected after its performance in London four years ago. But for anybody who predicted they couldn’t do it, the more they believed that they could. They head into the quarterfinal round with a 4-1 record.
"We've had a good set of pool games," United States coach Craig Parnham said. "We're disappointed with the result tonight, but overall and for the week, we've been very good. Huge amount of positives to come out of the week. Today's not the worst thing that can happen. We can learn some lessons from there, make sure we regroup and reset before the quarterfinal."
The Associated Press contributed to this report.