The 33-year-old Australian attacker injured his right ankle while playing for New York Red Bulls over the weekend and confirmed on Twitter on Monday that he would not join the Socceroos in Brasilia for their friendly international set for September 7.
 
Cahill had initially cast doubt on his chances of travelling after Saturday's match between the Red Bulls and DC United, having been substituted just before the hour mark after he copped a knock to his right ankle.
 
And the former Everton player, who has scored 28 goals in 63 matches for Australia, made the decision to pull out of the Socceroos' squad after the ankle did not respond quickly enough to treatment.
 
"Unfortunately I won't be fit to join @Socceroos in Brazil this week due to injury," Cahill tweeted.
 
"But glad we got the 3 points for @NewYorkRedBulls."
 
With Cahill having pulled out of the Socceroos' squad, Australia's head coach Holger Osieck is expected to pick Josh Kennedy up front in Brasilia, while Central Coast Mariners striker Mitchell Duke would be a surprise selection.
 
Cahill was substituted in the 58th minute of the Red Bulls' 2-1 home win over DC United after rolling his right ankle, following a tackle from visiting defender Dejan Jakovic in the first half.
 
Jakovic slid into Cahill in the lead-up to Lloyd Sam's opening goal for New York after seven minutes and although the Australian played on to score the eventual winner in the 38th minute, he slammed the Canadian defender's tackle after the match.
 
"Shocking tackle but there's nothing I can do about it," Cahill told soccerbyives.net.
 
Cahill's goal was the Socceroos attacker's eighth of the 2013 MLS season.