Who'll start for the Socceroos?

This is it, the big one. The Socceroos have reached a second successive Asian Cup final and now face one of the most important matches in their recent history.

MATCH REPORT: Socceroos book spot in Asian Cup final

Can they turn the tables on group-stage conquerors South Korea and lift major silverware on home soil?

Ange Postecoglou has used all but three of the 23 players named in his squad for the tournament, with back-up goalkeepers Mitch Langerak and Eugene Galekovic and young midfielder Terry Antonis the only men unfortunate enough not to enjoy game time.

So which XI will he send out at Stadium Australia on Saturday night? The fitness of Ivan Franjic remains a concern, while at least one berth in the midfield appears up for grabs.

Goalkeeper - Mat Ryan 

Ryan was assured of his place before the semi-final against the United Arab Emirates and nothing has changed since then. 

The Club Brugge goalkeeper didn't have a lot to do during the 2-0 win in Newcastle but acquitted himself well when called upon. 

The former Central Coast man can expect to be considerably busier in the final, playing against one of only two teams to breach the Socceroos' backline during the tournament.

The 22-year-old could yet prove to be the difference between Australia winning or losing the Asian Cup final. Let's hope it's the former.

VIDEO: See some of Mat Ryan's best saves from the Group Stage

Socceroo Mat Ryan alongside teammate Trent Sainsbury.

Defence - Ivan Franjic/Mark Milligan (RB), Trent Sainsbury (CB), Matthew Spiranovic (CB), Jason Davidson (LB)

As expected, Spiranovic made an immediate return to the backline after serving a one-match suspension in the quarter-final against China. He picked up where he left off with partner Trent Sainsbury, who headed the Socceroos in front early on at Hunter Stadium. 

The two were excellent in the semi-final, helping to keep out a UAE side who enjoyed plenty of possession but rarely threatened meaningfully, thanks in no small part to the dynamic duo guarding Ryan's goal.

The questions arise at fullback. It's likely Davidson will retain his place at left-back after scoring against the UAE, although Ange Postecoglou preferred Behich in the group-stage meeting with South Korea.

On the other flank Franjic is in doubt due to the hip injury he sustained last time out. Scans have cleared the 27-year-old of serious injury, but it remains to be seen if he will be passed fit to play. 

Should he fail to recover in time, and with Chris Herd already ruled out due to an Achilles injury, Postecoglou seemingly has two choices. 

One is to move Sainsbury across to right-back and deploy Alex Wilkinson at centre-back. The other is to play Mark Milligan at right-back. We think the coach's preference will be to not disrupt his centre-back pairing and call on the Melbourne Victory captain to step in for Franjic.

Midfield - Mile Jedinak, Massimo Luongo, Matt McKay

Skipper Jedinak is a certain starter as the lone holding midfielder, while Luongo, one of Australia's players of the tournament, is also guaranteed to play, barring injury. 

That leaves one remaining place ahead of Jedinak and alongside Luongo and we can't pick it. Mark Bresciano and Milligan struggled when they started against China and the UAE respectively, while McKay had an indifferent game against South Korea in Brisbane.

James Troisi started there in the tournament opener against Kuwait, before dropping out of the XI against Oman. He was then picked in a wide left role for the loss to South Korea, before coming on as a substitute against China and UAE.

That leaves the third midfield berth wide open. We're opting for McKay on the basis the Brisbane Roar man offers the most energy and the best balance between defence and attack. 

Attack - Robbie Kruse, Tim Cahill, Mathew Leckie

VIDEO: See a compile of Cahill's best goals for the Socceroos

The forward line picks itself, with only fitness concerns or illness preventing the same front three from starting again at Stadium Australia.

Cahill, attempting to match his heroics from the quarter-final, didn't have his best game against UAE, but worried their defence enough to create the space for Sainsbury and Davidson to score the decisive goals. 

Leckie was his usual industrious self while Kruse has been one of Australia's best players at the tournament.

Perhaps crucially, none of that trio started the 1-0 loss to South Korea in Queensland, a match in which the Socceroos created plenty of chances and could have won, even though the attacking big guns only came off the bench mid-way through the second half.

Having them there right from the off could be vital on Saturday night.

The Socceroos will face Korea Republic in the AFC Asian Cup Final at Stadium Australia on Saturday 31 January (8.00pm local kick off). Click here to purchase tickets.