PARIS, France -- Reigning champions Latisha Chan of Chinese Taipei and Ivan Dodig of Croatia will have to work their way through the draw as an unseeded pair if they hope to defend their mixed doubles title at Roland Garros.

Former WTA doubles World No.1 Chan and Dodig were the No.2 seeds when they picked up the title in Paris last year, a first mixed doubles Grand Slam championship for either of them. This year, they fall outside the eight seeded teams, and could face up to four seeded duos if they want to make it two in a row.

VIEW: The full mixed doubles draw at the Roland Garros website

In the first round, Chan and Dodig face another major-winning unseeded pair, Abigail Spears of the United States and Colombia's Juan Sebastian Cabal, who claimed the 2017 Australian Open title together.

The victors of that match could face No.8 seeds and 2017 French Open finalists Anna-Lena Groenefeld of Germany and Colombia's Robert Farah in the second round. Potential opponents Cabal and Farah have been one of the top men's doubles teams on the ATP Tour for quite some time, winning the Rome title for the last two years.

Read more: 2019 French Open women's doubles draw preview

With such quality found in the unseeded teams, the seeded pairings are evidently tremendously formidable. The draw is headed by No.1 seeds Nicole Melichar of the United States and Bruno Soares of Brazil. Melichar won the mixed doubles title at Wimbledon last year with Alexander Peya, while Soares has earned three Grand Slam mixed doubles titles in his career.

In the opening round, though, Melichar and Soares face an unseeded team with a stunning Roland Garros mixed doubles pedigree: former French Open mixed doubles champions Lucie Hradecka and Rohan Bopanna. Hradecka won the title in 2013 with Frantisek Cermak, and Rohan Bopanna was the champion in 2017 partnering Gabriela Dabrowski.

Dabrowski of Canada teams up with Mate Pavic of Croatia as the No.2 seeds. They reached the final together last year in Paris as the top seeds, before falling to Chan and Dodig. Dabrowski and Pavic also won the 2018 Australian Open as a tandem. Dabrowski is seeking her third straight trip to the Roland Garros final dating back to her 2017 title run alongside Bopanna.

Barbora Krejcikova of the Czech Republic and Rajeev Ram of the United States are the No.3 seeds, and are in the bottom half of the draw with Dabrowski and Pavic. Krejcikova and Ram are the only team in the running for the Calendar Slam this year, as they picked up the Australian Open title in January.

The Dutch duo of Demi Schuurs and Jean-Julien Rojer are seeded 4th, and find themselves in the top half with Melichar and Soares. Rojer won the mixed doubles title in 2014, partnering Groenefeld.

If seeds hold, the projected quarterfinals in the top half would pit top seeds Melichar and Soares against No.7 seeds Alicja Rosolska of Poland and Nikola Mektic of Croatia, and 4th seeds Schuurs and Rojer against No.8 seeds Groenefeld and Farah.

In the bottom half, the seedings project quarterfinal meetings pitting No.3 seeds Krejcikova and Ram against 6th seeds Chan Hao-ching of Chinese Taipei and Austria's Oliver Marach, and 2nd-seeded Dabrowski and Pavic versus No.5 seeds Zhang Shuai of China and John Peers of Australia.