Robson was broken four times and converted only one of her own five break points against fellow qualifier Dominguez Lino.
Robson, still only 18 years of age, won mixed doubles silver with Andy Murray at the London Olympics and had since benefited from an upsurge of singles form. A week ago at the Guangzhou International Open she became the first British female to reach the final of a WTA Tour event since Joe Durie in 1990.
Spaniard Dominguez Lino, ranked 64 in the world to Robson's 60, is rewarded with a last-16 match against Agnieszka Radwanska of Poland. The third seed moved on with a 6-2 6-3 victory over wildcard Zhang Shuai.
World number one Victoria Azarenka enjoyed a 6-4 6-2 win over unpredictable German Sabine Lisicki.
After withdrawing from Tokyo last week through illness, the Belarus player enjoyed a quickfire win over Alizé Cornet on Monday and progressed to the last 16 in 80 minutes, breaking her opponent on five occasions.
Eighth seed Sam Stosur fell 7-6 4-6 7-5 to Julia Goerges 7-6 4-6 7-5 to dent her hopes of reaching the WTA Championships in Istanbul.
Fifth seed Angelique Kerber of Germany blasted past Spain's Lara Arruabarrena Vecino 6-2 6-0. Seventh-seeded Chinese Li Na eased past Nadia Petrova of Russia 6-1 6-2 while ninth seed Marion Bartoli of France beat Japanese Ayumi Morita 6-4 6-3.
Caroline Wozniacki, the 10th seed who recently ended her 13-month title drought in Seoul, took nearly three hours to defeat Hsieh Su-Wei 6-7 7-6 6-0 while former world number one Jelena Jankovic was a 6-2 6-1 winner against Monica Niculescu and Romina Oprandi triumphed 7-5 6-2 over Camila Giorgi.