“During practice two days ago, after a wrong move he felt pain in his right knee. He has problems with the ligaments,” the Croat said.
Ivankovic told Reuters Iran had already contacted FIFA to replace him with Hadi Shakoury in case he could not play.
“We have made the contacts with officials because there is the 24-hour rule and so if Zare cannot play then we are allowed to call up Shakoury.”
Teams can call up replacements until up to 24 hours before their first game.
Zare was expected to start against Mexico, Ivankovic said.