Hong Kong's leadoff hitter Wing Hin Ng was the inspiration for her team's victory with two runs as they recovered to win.

It was the first time they had been ahead in the match since the bottom of the second inning.

The United States beat Australia 3-2 and had good reason to be grateful to pitcher Elise Berger.

In her 84 pitches, she allowed only two hits and one run and also achieved a strikeout. 

In the third inning, three consecutive hitters gave the United States the advantage and though the Australians scored twice in the sixth, they were unable to make any further breakthrough.

Host nation Canada began their campaign with an emphatic 9-1 win over Mexico, a victory which came despite a 90-minute weather delay in the third inning.

Before the bad weather arrived, it had been a close contest with the Canadians leading 2-1 but they extended their advantage scoring six runs to establish an unassailable advantage in the fourth inning immediately after the break.

Madison Willan led the Canada charge with four runs batted in and two runs scored.

In the next round of group matches, United States face South Korea.

Mexico and Australia, who both lost their opening encounters, meet in the afternoon, before Canada complete the day against Hong Kong.

Competition in World Cup Group A continues until August 12.