Halep, seeded third, was on the court just 51 minutes in a 6-3, 6-0 rout of Sesil Karatantcheva. Halep broke up a relatively close match by winning the last eight games.
Two of the three games Halep dropped were on serve but she won 70 percent of the points when Karatantcheva served and converted seven of her nine break opportunities. She lost eight points total in the second set.
No 4-seeded Annika Beck handled Tadeja Majeric 6-1, 6-2 in 57 minutes. Beck won nearly two-thirds of the points overall and, like Halep, recorded seven breaks.
Fifth-seeded Johanna Larsson stopped Lara Arruabarrena 6-2, 7-5, winning more than half (36-of-71) of the points off Arruabarrena's serve, and No. 7-seeded Maria-Teresa Torro-Flor beat Nina Bratchikova 6-1, 7-5.
In the only match Monday to go three sets, wild-card Agnes Bukta got by Sandra Zahlavova 6-1, 4-6, 7-6 in 2 hours, 50 minutes.