Caroline Wozniacki and Karolina Pliskova passed endurance tests to reach the final after winning two matches apiece at the rain-affected Qatar Open on Friday.
Wozniacki experienced a resurgence last season and the former world number one will play in her first final of 2017 on Saturday as a result of victories over Lauren Davis and Monica Puig.
The unseeded Dane took yet another weather delay in her stride to defeat qualifier Davis 7-5 6-1 at the quarter-final stage and returned late in the evening to knock out Puig.
It was after midnight in Doha when the indefatigable Wozniacki sealed a 6-1 6-2 win over the Olympic champion, who made 20 unforced errors and was broken seven times in a one-sided contest which lasted just 70 minutes.
Puig beat Daria Kasatkina, who claimed the scalp of Angelique Kerber in the second round, to set up a meeting with Wozniacki but the Puerto Rican could go no further.
World number three Pliskova made light work of sending Zhang Shuai packing 6-2 6-0 and returned to see off third seed Dominika Cibulkova to stay in the hunt for a second title of the year.
Cibulkova had already sealed her place in the semi-finals on Thursday, but was not able to benefit from having fresher legs as the second seed won 6-4 4-6 6-3.