The conclusion to the match was delayed again on Thursday by about four hours but when the red-hot Romanian finally returned to the court, she wasted little time sealing the deal.
World number one Halep will not have much time before her round of 16 clash against Australian 16th seed Ashleigh Barty, as the duo are scheduled to cap the evening session.
Bertens stuns world number one Halep for Cincinnati title
Halep owns a 1-0 career record against Barty, with the win coming last week in the semi-finals at Montreal where the French Open champion went on to capture her third title of the season.
American wildcard Amanda Anisimova and Croatian qualifier Petra Martic were battling for the final spot in the round of 16 but their match, which also began on Wednesday, resumed briefly on Thursday before rain once again stopped play.
WATCH: Halep hits outrageous tweener in Cincinnati final
Halep to meet Bertens for Cincinnati title