RIO DE JANEIRO (AP) — The Rio Open has lost some of its top players in early matches as it competes for attention during Carnival week in Brazil.
Top-seeded Kei Nishikori was ousted in the first round of the clay-court tournament by local favorite Thomaz Bellucci.
"It could be the worst match in the last few years," said Nishikori, who shattered his racket in anger during the match.
Last year's champion and third-seeded Pablo Cuevas was also beaten in the first round. So was Guido Pella, who lost to Cuevas in last year's final.
Of the eight seeded players, five lost in the first round.
That opens the door for No. 2-seeded Dominic Thiem to win his eighth ATP singles titles. Thiem defeated Dusan Lajovic of Serbia on Wednesday 6-2, 7-5 to reach the quarterfinals.
He said Nishikori's surprise exit "doesn't change anything."
"The tournament is strong," he said. "If you're not 100 percent you can lose to anybody. Everybody is very strong."
No. 5 Albert Ramos-Vinolas reached the quarterfinals by beating Fabio Fognini 6-2, 6-3.
Two Argentines also reached the last eight. Diego Schwartzman defeated countryman Federico Delbonis 6-4, 7-6 (1), and Nicolas Kicker had a 6-3, 6-3 win over Arthur De Greef.
The tournament needs all the promotion it can get. It's being held in Rio de Janeiro during Carnival week, which overwhelms everything else; a bit like the runup to the Super Bowl as Rio's famous parades start Friday in the Sambadrome.
The tournament is also without 14-time Grand Slam champion Rafael Nadal, who has been the top-seeded player here the last several years and a large draw but chose not to play this time.