Yoshihito Nishioka made it eight wins from his first 10 matches this year after defeating Oscar Otte 6-3 0-6 6-4 in Monday's opening round at the Delray Beach Open.

Nishioka was the highest seed in action on the first day of the tournament, and he had his back up against the wall after failing to win a game in a troubling second set, but produced three breaks of serve in the back-and-forth decider.

Meanwhile, Ecuador's Emilio Gomez earned a shot at top seed and world number seven Taylor Fritz after advancing 7-6 (7-3) 6-4 against Taiwan's Tung-lin Wu.

Portugal's Nuno Borges continued his winning run after earning his spot through the qualifiers, eliminating America's Steve Johnson 6-4 3-6 6-4, but the crowd got something to cheer for when the USA's Denis Kudla got the better of Australia's Jordan Thompson 3-6 6-4 7-6 (7-2).

Further south at Argentina's Buenos Aires Open, Serbia's Laslo Djere booked a blockbuster showdown against world number two Carlos Alcaraz after repelling the challenge of Italy's Fabio Fognini 6-4 6-4.

Argentinian Pedro Cachin put on a show for his hometown fans with a 7-6 (7-2) 6-4 victory over Brazil's Thiago Monteiro, but Cachin's compatriot Guido Pella had less success with a 6-4 7-5 defeat at the hand of Spain's Jaume Munar.