Tsitsipas broke for 2-0 and held clinically through to 6-3, with Duckworth's sole resistance a deuce hold for 3-5 saving both break points.
Tsitsipas broke for 4-3 to seal 6-4, though Duckworth mounted defiant resistance with a 10 minute hold for 2-1 saving all break points and another for 1-0.