Ajla Tomljanović through to Austin semifinals as Daria Saville triumphs in Mexico

Ajla Tomljanović has reached the semifinals of the Austin WTA Tour event. (Getty Images: Daniel Pockett)

In short:

Ajla Tomljanović defeated Ena Shibahara 7-5, 3-6, 7-6 (10/8) in Austin.

Daria Saville reached the Mérida Open after Paula Badosa retired.

What's next?

Tomljanović next faces top seed Jessica Pegula, while Saville plays Emiliana Arango in Mexico.

Australia's Ajla Tomljanović and Daria Saville have advanced to the semifinals of their respective WTA Tour events.

In Austin, Texas, Tomljanović claimed a dramatic quarterfinal victory on Saturday AEDT.

And in Mexico, qualifier Daria Saville advanced to the last four of the Mérida Open when Spaniard Paula Badosa, the second seed, was forced to retire.

Tomljanović surged to a 5-2 lead in the final set of her quarterfinal against Ena Shibahara but needed eight match points to clinch victory.

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The Japanese qualifier, who had upset Australian Kim Birrell in the previous round, pushed Tomljanović to a final-set tiebreak.

But Tomljanović closed out the match to win 7-5, 3-6, 7-6 (10/8) after more than two and a half hours on court.

Tomljanović next faces top seed Jessica Pegula, who scored a 6-2, 6-2 win over Russian Anna Blinkova.

World number 111 Tomljanović was given a wildcard to the event.

Saville, ranked 121, trailed 1-6, 5-3 when Badosa retired with a back injury.

She next plays Colombian qualifier Emiliana Arango.

Saville's victory kept the Australian flag flying in Mexico, after teen sensation Maya Joint's run was ended by world number 45 Elina Avanesyan.

Avanesyan fought back after losing the first set to win their quarterfinal 4-6, 6-2, 6-0.

AAP