A hat-trick to veteran striker Jermaine Beckford was the cornerstone to the ruthless 4-0 thrashing at Wembley Stadium.
The heavy defeat will almost certainly confirm Luongo's exit from Swindon when the transfer window re-opens, with the classy midfielder in demand after rising to prominence with a starring role in Australia's AFC Asian Cup 2015 triumph in January.
Melbourne-born Luongo had little opportunity to shine in a team that was thoroughly outplayed by Preston, but still displayed his tireless work rate.
Luongo has been strongly linked with Premier League outfit Aston Villa, where his former youth coach at Tottenham Hotspur, Tim Sherwood, is in charge.Sherwood was on hand to watch Luongo a fortnight ago in Swindon's play-off semi-final clash with Sheffield United.
If Villa doesn't come calling, the 22-year-old is unlikely to want to spend another season in England's third-tier competition and is certain to have suitors in the Championship, if not the Premier League.
Swindon manager Mark Cooper acknowledged as much when asked whether it would be possible to keep the youngster, as well as goalkeeper Wes Fodringham and midfielder Ben Gladwell.
"It will be difficult, we know that," Cooper said.
"We have to start again. People will come, people will go, but we'll start again."
Two players who have already earned their place in the Championship are Wright and Kilkenny.
Kilkenny, who last played for the Socceroos in 2011, created several opportunities from set pieces while 22-year-old Wright showed the reliability in defence which has led to him cracking into the Socceroos squad in the past 12 months.
Preston took a two-goal lead in the opening 15 minutes before removing all hope just before half-time with Beckford's second goal a delightful, curling left-footed effort to give it a 3-0 advantage at the break.
Beckford scored 12 minutes into the second half to complete his hat-trick.