Novak Djokovic overcame a shaky start to beat Frenchman Quentin Halys on Thursday and reach the Adelaide International quarter-finals, stepping up his preparations for the Australian Open.

The top seed from Serbia won 7-6 (7/3), 7-6 (7/5) and will face Canada's Denis Shapovalov in the last eight.

Djokovic returned to the scene of his 2007 title run on Tuesday with a comfortable straight-sets win over France's Constant Lestienne.

He backed that up against Lestienne's doubles partner Halys but was slow to get going, slumping 2-5 in the first set before clinching victory.

"It was a great performance from my opponent today," said the 35-year-old Djokovic, who is warming up for a tilt at a 10th Australian Open title after missing last year's Grand Slam when he was deported over his vaccination status.

"He played like a top-10 player today.

"It was difficult to break his serve because he was hitting his spots and he was being very precise, and big serves, as well," he added.

"Proud to be able to overcome a challenge like this. Winning two tiebreakers is always great I think for confidence level at the beginning of the year."

With the crowd firmly behind the former world number one on a packed centre court, Djokovic -- who won Wimbledon among five titles last year -- lost his opening service game against the 64th-ranked Frenchman.

He earned two break points in game three but was unable to convert, biding his time until the seventh game, when he broke to love and then raced through the tiebreak.

Nothing separated them in the second set, which again went to a tiebreak, after Halys saved two match points at 5-4, with Djokovic finally prevailing when Halys netted a backhand.

Djokovic's reward is a clash with world number 18 Shapovalov, who sailed into the last eight with a 6-4, 6-3 win over Russian qualifier Roman Safiullin.

Djokovic has won all seven previous encounters with the Canadian.

Shapovalov is still riding the wave of leading Canada to the Davis Cup title and said he was determined to maintain his good form.

"Definitely trying to implement that on the individual side. Obviously so far it's been a great start. Hopefully I can capitalise on a good start to the week and definitely excited for what's to come," he said.

American Sebastian Korda progressed by beating Spain's Roberto Bautista Agut 6-4, 6-4 to set up a clash with Italian sixth seed Jannik Sinner who ousted defending champion Thanasi Kokkinakis 7-6 (7/2), 6-4.

Azarenka triumphs

In the women's draw, Czech teen Linda Noskova defeated American Claire Liu 6-2, 6-2 to power into the last eight, where she will play two-time Australian Open winner Victoria Azarenka who overcame Zheng Qinwen.

"She's a great talent. I feel like she's going to be a really, really good player," Azarenka said of the rising Chinese player after using her experience to beat her 6-2, 7-5.

"But I thought that I stuck to my game plan pretty well today."

Former French Open winner Jelena Ostapenko crashed out 6-3, 6-0 to Romania's Irina-Camelia Begu, who will face Russian world number nine Veronika Kudermetova next.