Troisi, a second-half substitute for the injured Robbie Kruse, proved to be the Socceroos' hero as he scored in the first half of extra-time to seal a gripping 2-1 win at ANZ Stadium.
"It was just an amazing night," an ecstatic Troisi told reporters afterwards.
"The boys played so well and to win this trophy means so much.
"It was great score the goal and be a part of it and create history for Australian football but it's a team effort and it's not just about me.
"We showed our Australian spirit tonight. We weren't going to lose."
Troisi's goal – which came in the 105th minute – was a result of some brilliant work by fellow substitute Tomi Juric down the right.
The Western Sydney Wanderers striker was knocked to the ground in possession but got back up and beat two defenders with a classy back-heel through the legs.
His cross was spilled by Korean goalkeeper Kim Jin-hyeon, with Troisi on hand to slam it home from close range.
"I didn't know what was going on to be honest. I thought it was a free kick to start with but the ref didn't give it," Troisi explained when asked about the move leading up to the goal.
"I just basically stayed on my toes and the keeper dropped it and I pounced on it."
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