The US, who are the three-time defending champions, defeating the Dominican Republic in each final from 2017 to 2019, came from one set down to beat Mexico 21-25, 25-17, 26-24, 29-27 in Santa Domingo in the Dominican Republic.

Veronica Perry scored a match-high 27 points, including four aces.

US coach Karch Kiraly said: "Our team battled hard, I am very proud. 

"It wasn’t easy but our side knew how to play as a team. 

"I hope we keep improving in the next games."

The other pre-event favourites, the Dominican Republic, also got off to a strong start, sweeping past Cuba in a comfortable 25-17, 25-12, 25-20 victory.

Yonkaira Peña led the winners - and the match - in scoring with 13 points, the only player to top double figures.

"At the beginning of the tournament there is always some stress, but I think we had a good start," Dominican Republic head coach Marcos Kwiek said. 

"We played well-focused, which is the important thing. 

"We knew the Cuban team was a young one, so we have to press them and everything went well."

In the opening game of the day - and the tournament - Canada defeated Puerto Rico in straight sets, winning 25-17, 25-16, 25-18.

Nyadholi Thokbuom led Canadian scorers with 15 points, five of which came from blocks, and Hillary Howe added 10 points.

"It was a good game for us," Canadian captain Brie King said. 

"Some of our players are experiencing their first international competition. 

"We gave them the confidence and they followed the instructions to win the match."

The Championship continues tomorrow with Cuba against Canada, the US versus Puerto Rico and the hosts playing Mexico.