Benjamin Becker recorded a straight sets victory against Lukas Lacko at the US Indoor Championship to set up a second round meeting with defending champion Kei Nishikori of Japan.
The German saved all three break points that he faced in beating Slovakia's Lacko 6-3 6-2 to advance through to a clash against the top seed.
Nishikori, who like the other top-four seeds received a first-round bye, defends his Memphis crown after helping Japan beat Canada in the first round of the Davis Cup earlier this month.
Cypriot wildcard Marcos Baghdatis, who reached the Australian Open final in 2006, beat US qualifier Rajeev Ram 6-3 6-4 to book a second-round date with Australian third seed Lleyton Hewitt.
Baghdatis, ranked 134th in the world, has not won two matches in a row since last year's US Open, when he lost in the third round to Stanislas Wawrinka, who went on to win the Australian Open earlier this year.
Since then, Baghdatis has lost eight of his past 10 matches but against Ram he was lethal, firing 10 aces and dispatching his opponent in just 75 minutes.
Croatian Ivo Karlovic blasted 14 aces to beat Aussie Matthew Ebden 7-5 6-4 and advance to a second-round meeting with Spanish second seed Feliciano Lopez.
Kazak eighth seed Mikhail Kukushkin advanced after defeating Russian Teymuraz Gabashvili 7-6 (11/9) 7-5.
Kukushkin could face Taiwanese fourth seed Lu Yen-Hsun in the quarter-finals.