The opening match set the tone for the evening when tennis coach Andres Schneiter knocked out men’s world number 34 Corentin Moutet.
The upsets kept on coming across the quick-fire format as fellow players offered enthusiastic support from the side of the court and the crowd rallied behind the underdogs.
Garland, who was beaten in the first round of singles qualifying in Melbourne, appeared more stunned than anyone as she beat former women’s world number three Maria Sakkari and 2024 Wimbledon semi-finalist Donna Vekic.
Smith, meanwhile, did not need to hit a ball against Sinner after the men’s world number two failed to land his serve – with professionals only granted one opportunity to get it right.
He was not done there, following up victory over Anisimova by beating 71st-ranked Spaniard Pedro Martinez to set up his shot at the prize money.
“Coming into tonight I would have been happy winning just one point,” said Smith.
“I was so nervous but enjoyed being out here, it was a great experience.”
Elsewhere, Sakkari ended Alcaraz’s bid after the top-ranked men’s player netted an attempted drop shot.
Meanwhile six-time major winner Iga Swiatek saw off the men’s world number 22 and 31 in Flavio Cobolli and Frances Tiafoe respectively before losing to Martinez.