Valeri is sidelined with a lower-leg syndesmosis injury for the next four months and won't play any part in the crucial final stage of qualifying.

The Socceroos could badly do with the 28-year-old's poise and influence in the centre of the park as they enter a torrid dogfight to punch their ticket to next year's World Cup in Brazil.

Holger Osieck's men are tied for second in their group, on five points with Iraq and Oman. Jordan is only a point further back and in the mix for the final automatic berth.

In the Socceroos' favour, they have three of their last four games at home, starting with the match with Oman at ANZ Stadium on March 26.

Valeri, on crutches and wearing a moon boot on his left leg, has complete faith that the Socceroos, who will be without captain Lucas Neill for the Oman game due to a one-match suspension, can get the job done and qualify for their third successive World Cup.

''I believe we're going to get to the World Cup and we're going to take it to them in Brazil,'' Valeri said.

''We had a rough start and have managed to pull through.

''Neither Lucas nor I will be there for the Oman game, but anyone can do well with the way the team's structured.''

Valeri was at the Holy Trinity Primary School in Curtin on Friday as an ambassador for the 14th annual Canberra Catholic Primary School Soccer Carnival, to be held at the University of Canberra on March 24.

The severity of Valeri's injury came as a surprise after he limped off in his 50th appearance for the Socceroos in last November's friendly with South Korea.

Three months after showing no improvement, the Tuggeranong United junior had an operation in Sydney to fix the displacement in his fibula and tibia.

Valeri hopes to be back on the training paddock in July, in time for the start of pre-season with Italian club Sassoulo, which is on track to earn promotion to Serie A.

''It's unfortunate, but I've got full confidence in the players that are going to be replacing me and the coach and his mentality,'' Valeri said.

''There are a lot of players, like myself, Alex Brosque, Brett Holman, Mile Jedinak, who went from being the younger blokes into the team to being the older guys. Everyone's adapting to new roles and we're getting similar results to the old generation of Socceroos.''

One of that new breed is fellow ACT product Tom Rogic, who made his international debut on the same night Valeri reached his half-century.

Rogic has made a blistering start with Scottish powerhouse Celtic and looms as an X-factor for the Socceroos.

''He's a great player who has a lot of potential,'' Valeri said.

''He's big, he's technically gifted and he's able to score.

''It's always tough to judge a young player when they go overseas, but he'll do well.''