The 16-year-old qualified for the under-18 event in Singapore last October by winning his two matches two days before the main event.
“I was hopeful leading into it but surprised myself how far I went into the tournament,” Harding said.
The Christ Church Grammar School Year 11 student, who helped his school win the Corr Cup last year, said he had developed his game in the past few years.
“My game’s matured from just having baseline rallies to cutting off points with forehands and volleys and a big serve,” Harding said.
The Dalkeith resident watched several matches at the Hopman Cup last week, reminiscing about his ball kid duties at the tournament two years ago.
“It was really great seeing all the top players close up like (Andy) Murray and (John) Isner… I was trying to catch his serve,” Harding said.