QUITO, Ecuador (AP) — Gerald Melzer of Austria upset No. 6-seeded Horacio Zeballos of Argentina 6-7 (4), 6-3, 7-6 (4) on Monday to reach the second round of the Ecuador Open.

The clay-court tournament is the first of five across Latin America, The other stops are in Buenos Aires, Rio de Janeiro, Sao Paulo, and Acapulco, Mexico.

Ivo Karlovic of Croatia is the top seed in Quito with Albert Ramos-Vinolas of Spain at No. 2. None of the top four seeds played on Monday, and all have byes into the second round.