As a result, the 2025 Shanghai champion, Vacherot, advances to the quarter-finals. The Monegasque player will next face either top seed Alejandro Davidovich Fokina or Australian Rinky Hijikata.

Davidovich Fokina will play Hijikata on Wednesday evening on centre court.

Kokkinakis made his highly anticipated return to singles action on Monday evening, after nearly 12 months away following surgery to address a long-standing pectoral problem.

The home favourite suffered a flare-up of his shoulder injury but defied the pain to secure a gallant victory in his first singles match in almost a year at the Adelaide International.

In his first singles outing since January 15 last year, the South Australian played through pain to finish his comeback match, battling past Sebastian Korda in a final-set tie-break, but visibly struggled with his right shoulder throughout the match.

"It's tough. Obviously my right arm caused by serving has plagued me my whole career. There's a lot of what ifs, especially in my mind, if I wasn't struggling with that. I know little niggles are normal here and there, but I feel like kind of what I've gone through is a little bit out of the normal," Kokkinakis said after his match.

"It's tough mentally. I spent all year rehabbing, trying to get it right. I had a surgery. It was a slightly different pain to last year. I'll see how I wake up tomorrow. But, yeah, it's tough. It puts a dampener on the win for sure," he added.

Last February, Kokkinakis had a donor Achilles tendon attached to his right pectoral muscle and shoulder. As the first tennis player to undergo such surgery, he made his competitive return in doubles with Nick Kyrgios last week at the Brisbane International.

"It's tough mentally. I spent all year rehabbing, trying to get it right. I had a surgery. It was a slightly different pain to last year. I'll see how I wake up tomorrow. But, yeah, it's tough. It puts a dampener on the win for sure," he added.

Kokkinakis has a protected ranking that allows him to enter the Australian Open singles from January 18 and is also scheduled to play doubles with Kyrgios. However, his participation in the season's first major is now in serious doubt.