The world no. 1 Djokovic had surgery on his right wrist following the Australian's 6-4 6-4 victory in Perth.
Eleven days before he starts to defend his Australian Open title on January 14, it was the Serb's first loss in Australia since 2018.
Australia won the tie when Ajla Tomljanovic defeated Natalija Stevanovic in the second match.
In the final four, they will face either Greece or Germany.
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