Pablo Carreno-Busta and Blaz Rola were among those to cause upsets in the first round of the Brasil Open.
The seeds tumbled in the first round of the Brasil Open on Tuesday as Albert Ramos, Paolo Lorenzi, Nicolas Almagro and Pablo Andujar all bowed out.
Ramos was the highest-ranked casualty to be dumped out in Sao Paulo, but there was no sign of things to come when he whitewashed Pablo Carreno-Busta in the opening set.
Wednesday's second-round action of the Brasil Open has been postponed without a match being completed.
Contests between Inigo Cervantes and Blaz Rola on centre court and Daniel Gimeno-Traver and Pablo Carreno Busta started but could not be completed before rain suspended play.
Lucky loser Roberto Carballes Baena continues impressive run in Brasil Open
Roberto Carballes Baena defeated second seed and local favourite Thomaz Bellucci to continue his impressive run in the Brasil Open, booking a place in the quarter-finals.
The 22-year-old, a lucky loser, won 2-6 6-4 6-3 on the Sao Paulo clay to reach his second ATP World Tour quarter-final.
Unseeded Argentines Guillermo Duran and Andres Molteni made a quick start and held off top-seeded Brazilians Marcelo Melo and Bruno Soares 6-1, 2-6, 10-8 in the quarter-finals of the Brasil Open in Sao Paulo on Friday. Each team broke serve twice in the 71-minute match, but the eventual winners only dropped one point on serve in the Match Tie-break to move into the semi-finals.
Cuevas Wins Pablo Battle, Defends Brasil Open for 2nd Consecutive Title
While the field lacked any Top 20 players, Cuevas defended his title from last year and won his second consecutive claycourt title after the Rios Open, on Sunday beating Pablo Carreno Busta 7-6(4), 6-3 in the final of the Brasil Open.