Ashleigh Barty's 10th straight win has guaranteed her another career-high ranking and there may be even more significant gains to come.
A 6-1 1-6 6-1 win over Australian Open semi-finalist Danielle Collins thrust Barty into the third round of the Madrid Open and within sight of an all-important top-eight seeding for the French Open starting later this month.
Now guaranteed to climb from No.9 to No.8 in the rankings, Barty could conceivably surge to fourth in the world if she continues her hot streak in the Spanish capital.
The 23-year-old next faces unseeded Kazakh Yulia Putintseva for a place in the quarter-finals, having made a successful transition from hard courts to clay.
After dominating the first set against Collins, Barty found herself in trouble in the second before rallying to to close out Monday's match in an hour and 25 minutes.
Barty blasted 18 winners but threw in 19 unforced errors during the topsy-turvy encounter.
The Queenslander fired five aces but only made 55 per cent of her first serves while converting four of eight break-point chances.
Barty applied heavy pressure from the start, reeling off five games in a row to put Collins, who has only three WTA main-draw wins on red clay, on the back foot.
Collins responded by taking the last five games of the second set to level up the match.
But Barty regrouped and quickly rallied to a 3-0 lead before the world No.30 Collins got on the board in the final set.
The Australian No.1 continued her run by reeling off the final three games to set up her round-of-16 showdown with Putintseva, who beat Pauline Parmentier 6-4 4-6 6-3.
A winner of last month's Miami Open, Barty improved her 2019 win-loss record to 22-3 with her latest victory.
Defending champion Petra Kvitova, meanwhile, defeated 2017 finalist Kristina Mladenovic 6-3 7-6 (7-5) in her bid for a fourth title in Madrid.
The second-seeded Kvitova outlasted Mladenovic by winning the last three points in the tiebreaker to close out the match in nearly two hours.
"I'm glad I won the tiebreak. That is my kind of issue sometimes, but overall it was pretty tight," Kvitova said.
"I fought hard in the end."
Seventh-seeded Kiki Bertens defeated Jelena Ostapenko 6-4 6-3 to remain on track for a second-straight final in Madrid while eighth-seeded Sloane Stephens got past Victoria Azarenka 6-4 2-6 6-2.
Others to progress to the round of 16 were 12th-seeded Anastasija Sevastova, Belinda Bencic and Viktoria Kuzmova.
