Kimberly Birrell has gone from working at the Brisbane International to starring in it.

The radiant Gold Coast talent shed joyful tears on Wednesday after taking the scalp of world No.8 Emma Navarro on Pat Rafter Arena five years after an injured Birrell worked on the media team.

A year earlier Birrell had beaten Daria Kasatkina at her home event to notch a maiden top-10 scalp, but an elbow injury then put her career on ice for almost three years.

The 26-year-old, 113th-ranked wildcard was courageous and powerful in a fluctuating affair against the US Open semi-finalist and Brisbane second seed, winning 7-5 7-5 to sit one win away from a maiden WTA 500 quarter-final.

"It's pretty crazy," Birrell said.

"Working for the tournament instead of playing in the tournament ... I realised how big of a sport tennis is, and it was really cool to be on the other side and experience all of that.

"It gave me the chance to reflect and realise that I did really want to keep playing, and then obviously I didn't expect to be out, injured for so long.

"That (2020) was the beginning of my injury; I had almost two more years of rehab ahead of me.

"There were periods where I didn't know if I was going to get back on court, let alone at the level I played today."

Birrell will move inside the top 100 on the live rankings for the first time if she beats world No.35 Anastasia Potapova on Thursday.

She was part of Australia's Billie Jean King Cup team in November and made the Japan Open final in October.

But that resume wasn't enough for an Australian Open wildcard, Birrell forced to qualify such is the glut of local talent hovering just outside the top-100 automatic entry.

"It's probably one of the first years that it didn't really play too much on my mind," she said.

"We do have some amazing juniors coming up through the ranks and when I was their age, I was given some opportunities from TA.

"I qualified at the (2024) US Open, so I have belief that I can do it and can't wait to get to Melbourne ... and get there (to the main draw) on my own."

Australian 18-year-old Maya Joint, ranked 116 in the world, then threatened to upstage Birrell when she pushed former world No.1 Victoria Azarenka in the night session.

Joint was the first-set aggressor as she bossed the two-time Australian Open and Brisbane champion around the court.

Azarenka saved three set points to force a tiebreak but Joint hit four consecutive winners to jump clear and eventually clinch the set.

The veteran quickly levelled, winning 20 of 22 points at one stage before Joint regained her feet in the third set.

It was the teenager who made the first move, breaking to get within two games of a monumental upset.

But Joint blinked and Azarenka pounced to break straight back and escape into the fourth round with a 6-7 (7-5) 6-2 6-4 victory.