World number one Ash Barty faced a tough battle before she subdued Croatia's Petra Martic 7-6(6) 3-6 6-3 to reach the semi-finals of the Wuhan Open for the third consecutive year on Thursday.
Barty, ranked 21 places above her opponent, won 73% of her first service points and fired eight aces in a match that lasted two hours and 22 minutes.
The Australian took a 4-1 lead in the opening set where she won 15 consecutive points but squandered the advantage as Martic, who finished runner-up in Zhengzhou earlier this month, fought back to enforce a tiebreak.
Barty then made 13 unforced errors in the second set to open the door for Martic, who needed only one break of serve, to make a comeback and level the match.
Top seed Barty was broken again in the opening game of the final set before breaking back. She then won another break point when Martic double faulted before serving out the match.
In the other quarter-final, Ukrainian third seed Elina Svitolina was dispatched 6-1 6-3 by unseeded American Alison Riske.
Riske converted five of 13 break points and dropped serve only once in the contest to claim her third top 10 win of the year.
Fifth seed Petra Kvitova advanced to the semis with a 6-2 6-4 victory over Ukrainian teenager Dayana Yastremska while defending champion Aryna Sabalenka also went through with a 6-3 1-6 6-1 win over Kazakhstan's Elena Rybakina.