Diaz enters the competition as the top-ranked player with 5634 ranking points, but Zhang claimed the title in 2019 - with the 2020 championships cancelled due to COVID-19.

Diaz had won the previous two titles, while Zhang is the second seed this time with 4149 ranking points.

Canadian Mo Zhang, with 3887 points, is ranked third entering the competition.

The men's singles is set to be a battle of the Brazilians, with the South American country boasting the top three ranked players in the draw.

Hugo Calderano is the strong favourite with a massive 8464 ranking points to his name. 

No one is within half of the 2017 Pan American champion, with Gustavo Tsuboi second on 3790 with defending champion Vitor Ishiy third on 2822.

Zhang will not be able to emulate her four-title 2019 performance, when she won the singles, mixed doubles, women's doubles and team gold medal, but she will look to win the mixed doubles title alongside Kai Zhang, who she claimed the title with in 2019.

The US duo is only the fourth seed, and Ishiy and Bruna Takahashi of Brazil are the number one seeds.  

Ishiy is also one of the favourites in the men's doubles as the number two seeds with Eric Jouti, with the pair having won the title in 2017 and 2018.

Defending champions Gaston Alto and Horacio Cifuentes of Argentina, are the number one seeds.

The women's singles is led by the Diaz's of Puerto Rico - Adriana, who will be chasing the women's singles title, and Melanie. 

Brazil are the favourites to retain the men's team title, having won the competition every year thus far, while the women's team defending champions the US are also seeded first.

Competition gets underway tomorrow with the men's and women's singles quarter-finalists set to be determined.