Petra Kvitova will look to end a poor run against Ash Barty when the pair lock horns in the Qatar Open semi-finals.
An upset win over third seed Karolina Pliskova saw Ons Jabeur make more history in Doha on Wednesday.
Sofia Kenin's poor results continued on Tuesday, but Ash Barty had few problems reaching the last 16 in Doha.
Having triumphed in Doha last year, Elise Mertens kicked off the defence of her WTA Qatar Open title in style on Sunday.
Ons Jabeur pushed Simona Halep all the way, but the two-time grand slam champion was not to be denied a place in the last eight in Dubai.
Garbine Muguruza beat Kim Clijsters in the Belgian's first match since 2012, but the four-time major champion saw some positives.
Garbine Muguruza battled to victory against Kim Clijsters, who was playing her first competitive match for more than seven years.
Former world number one Kim Clijsters will face a tough assignment against Garbine Muguruza in her first professional match since 2012.
Garbine Muguruza has joined the field at the Dubai Tennis Championships, but Bianca Andreescu has pulled out of the WTA Tour event.
Russian-American Sofia Kenin could look to two of the biggest names in women's tennis for inspiration as she arrived on the big stage.