Sydney United 58, founded as Sydney Croatia in 1958 and a powerhouse in the National Soccer League that preceded the formation of the A-League in 2004, won 4-3 on penalties to reach the quarter-finals of the Australia Cup after the tie finished all square at 1-1.
Melbourne club Western United, who became champions of Australia in only their third season of existence in May, dominated the first half and took the lead through a 43rd minute Connor Pain volley but Tariq Maia equalised after the break.
Fans invaded the pitch at the Sydney United Sports Centre when Christian Gonzalez converted the decisive spot kick and former Manchester United goalkeeper Mark Bosnich was on hand to celebrate the triumph at the club where his career started.
The club helped nurture the talents of a string of other Socceroos, including current coach Graham Arnold, former skipper Mile Jedinak and all-time leading goalscorer Tim Cahill.
