Screens were set up on the pitch of the 6,500-seater Freshwater Stadium in Port Vila, allowing locals to watch Vanuatu's first professional footballer play the biggest game of his career.
"It means a lot," Kaltak, draped in the Vanuatu flag, told reporters. "We've been trying to get the breakthrough, getting kids overseas, not just Australia and New Zealand but to get professional. It just didn't happen.
"But now that I'm here and the first one, it's amazing.
"To be honest, back home in Vanuatu right now, it's like we won the World Cup, everyone just celebrating this moment."
CommBank Stadium even hosted Vanuatu prime minister Ishmael Kalsakau, who flew in for the occasion and embraced and congratulated Kaltak afterwards.
"I was so excited to see them here," Kaltak said. "I didn't even know they were here until one of the management came running up to me and said: 'Your prime minister is here!'
"Then it was just amazing to see them here."
Before earning his shot under Nick Montgomery, Kaltak played semi-professionally in Papua New Guinea, the Solomon Islands, Fiji, New Zealand and NPL South Australia.
But he has formed a killer central defensive partnership with young gun Nectarios Triantis, and the best appears yet to come for Kaltak, now signed until the end of the 2024-25 season
"It's crazy to think that this is their first real professional season," skipper and goalkeeper Danny Vukovic said. "Brian has been a revelation, as has Nectar.
"Who knows what Brian can do? That was his first season and he's been amazing."
But first, Kaltak will take a moment to relish how far he's come.
"I kept picturing us winning the final five months ago, when I came into the team I was picturing this moment," he said. "Now it happens, it's like a dream."