Australia's Jason Kubler has beaten former world No.7 Fernando Verdasco in straight sets in the opening round at the ATP claycourt tournament in Houston, Texas.
Sixth seed Kubler won 7-6 (9-7) 6-0 win over the 39-year-old Spaniard, a 2009 Australian Open semi-finalist who is now ranked No.232 in the world.
Both players were broken twice on the way to a first-set tiebreaker, which the Queenslander took at the fourth attempt.
World No.71 Kubler was almost faultless on serve in the second set and will take on Daniel Elahi Galan in the last 16 after the Colombian's 6-2 6-2 win over China's Zhizhen Zhang.
Australian qualifier Aleksandar Vukic was beaten 4-6 6-4 4-6 by Denis Kudla of the US in just shy of two hours.
Kudla will next take on another Aussie, Jordan Thompson, if the 84th-ranked Sydneysider can overcome American fifth seed J.J. Wolf in round-of-32 action on Tuesday.
Meantime, Australian's Alexei Popyrin has begun his adventure in Morocco with a 71-minute 6-3 6-2 victory over local Younes Lalami Laaroussi.
Popyrin's next test in Marrakech comes against second-seeded Brit Daniel Evans, who had a first-round bye.