Fearnley’s dominance calmed the home crowd at a packed John Cain Arena, which had noisily cheered Kyrgios on during memorable moments of his Australian Open career.
However, the atmosphere quickly turned sour as it became clear that Kyrgios was struggling.
Former world No. 13 Kyrgios, who is unranked and received a wild card, suffered an abdominal injury upon returning to the Brisbane International in early January.
This meant there were doubts whether he would play at all in Melbourne this week.
From the start of the match against Fearnley, Kyrgios lacked fitness, regularly clutching his stomach and twice requiring treatment in a chair.
Fearnley, who quickly rose into the top 100 players in the world last year, refused to be distracted by the problems his opponent was facing.
While Kyrgios recovered from a third-set breakdown, briefly stoking the crowd’s excitement, Fearnley escaped in the tie-break and advanced to the second round.
