Two Socceroos are sent home from the World Cup as Aussies worry about facing superstar Mohamed Salah in knockout clash

Socceroos stars Mathew Leckie and Jacob Italiano have succumbed to injury and been sent home from the World Cup as the Aussies sweat on the status of Egypt's superstar forward Mohamed Salah.

FIFA rules mean Leckie and Italiano can't be replaced with new additions to the squad after they missed the draw with Paraguay that gave the national team their third berth in the tournament's knockout stages.

Aziz Behich said he was 'gutted' for Leckie – but the team must now prepare for the possibility that Salah, who stamped himself as one of the true greats of the game during his time with Premier League giants Liverpool, will line up against them in the do-or-die clash at 4am Saturday, AEST.

Socceroos players and staff watched on Friday night as their potential opponent swapped multiple times before Egypt's dramatic 1-1 draw with Iran and Belgium's 5-1 thrashing of New Zealand sealed their opponent.

Australia will play Egypt, the runners-up in Group G, in Arlington, Texas – though there is a question mark over Salah, who came off and had his left hamstring iced after just 56 minutes.

'It didn't look good for him to come off in such an important game at 1-1, to come off at that moment, so you think there might be something there,' Socceroos assistant coach Hayden Foxe said.

Jacob Italiano (pictured executing a tackle against the USA at the World Cup) has lost his injury battle and is returning home from the tournament

His teammate Mathew Leckie (pictured) is also on his way back home to Australia

Former Liverpool superstar Mohamed Salah shapes as a huge obstacle for the Aussies if he's fit for their knockout clash with Egypt on Saturday morning, Australian time

'But he's a player of enormous talent and I'm sure he'll be doing everything that he can to play in this game.

'To try and combat them type of players, you don't put too much emphasis, but you have to respect that and you have to acknowledge that there are some talented players.

'And then you might play a way where you can force them into a wide area or an area where he's not getting a lot of the ball in between the lines.'

If Salah is fit, coach Tony Popovic could face a choice on whether to keep Aziz Behich on the left to mark him, or restore Jordy Bos to his natural side.

That would be a tough call given Bos's dynamic dominance on the right against Paraguay.

Salah is Egypt's undisputed headline act, supported by Manchester City forward Omar Marmoush.

The rest of the squad is less-heralded, but Foxe pointed to Egypt's superb qualification campaign, then strong warm-up friendlies against Brazil and Spain, as proof of their quality.

'They're a tough team. They play as a team. A lot of their players play in their local league, but their local league is strong,' Foxe said.

Salah will be a huge headache for Socceroos coach Tony Popovic (pictured) if he gets through his hamstring ailment

Egypt also boast Manchester City forward Omar Marmoush (pictured in red playing against Iran)

'They know each other. They've been together for a long period of time, so they play as a team, as a unit.

'And as we've shown, when you play as a team, as a unit, you're difficult to beat. So it's going to be an almighty game.'

Australia have only played Egypt twice, in 1987 and 2010.

But the Socceroos feel their tough AFC qualification route, which frequently involves playing west Asian opponents like Saudi Arabia, Bahrain and Jordan, will hold them in good stead as they eye a maiden knockout win.

'They have some real natural technical talent,' Foxe said.

'They play kind of fearlessly, which is a typical African-Arab kind of way of playing football.

'So it's going to be a good test, a challenge we're looking forward to.'