RIO DE JANEIRO - Defending champion Diego Schwartzman of Argentina became the latest high-profile casualty at the Rio Open on Wednesday, retiring hurt in his first-round match against Uruguay's Pablo Cuevas.

Fourth seed Schwartzman trailed 6-1, 4-1, when he quit because of a right leg injury. The match had been carried over from Tuesday due to rain.

His exit means each of the top six seeds departed in the first round of the ATP 500 event on the outdoor clay of the Jockey Club Brasileiro.

Top-seed Dominic Thiem, Fabio Fognini (2), Marco Cecchinato (3), Joao Sousa (5), Dusan Lajovic (6) were also seeking early flights home after defeats on Tuesday.

Meanwhile Jaume Munar of Spain beat Britain's Cameron Norrie 7-6 (6), 5-7, 7-6 (4), Bolivia's Hugo Dellien overcame Roberto Carballes Baena of Spain 7-5, 6-4, Aljaz Bedene of Slovenia defeated Brazil's Thiago Monteiro and Felix Auger-Aliassime beat Chilean Christian Garin 7-5, 6-4.