Top seeds Dominic Thiem of Austria, and Italy's Fabio Fognini and Marco Cecchinato were ousted in the first round of the Rio Open clay-court tournament on Tuesday.

No. 1-seeded Thiem lost to Serbia's Laslo Dere 6-3, 6-3, while the second-seeded Fognini was defeated by Canadian Felix Auger Aliassime 6-2, 6-3. Third-seeded Cecchinato, who won the Argentina Open on Sunday, was also eliminated by Slovenia's Aljaz Bedene 7-5, 7-6 (1).

Fifth-seeded Joao Sousa of Portugal defeated Argentina's Guido Pella 6-4, 3-6, 6-4. Dusan Lajovic, the No. 6 seed, lost to Britain's Cameron Norrie 6-2, 6-1.

Argentina's Diego Schwartzman, who is the fourth seed and defending champion, had his match suspended by rain.