The 30-year old, who has been with the Glory for eight seasons, is keen to get over to Sydney and help the Sky Blues in their ACL quest but he said the deal has to be completed by this afternoon.
"A decision hasn't been made yet and a deal has to be signed by tomorrow afternoon if it's going to happen," he told thewest.com.au yesterday.
"Sydney is a big club. They haven't had a good year but they have great resources, they are set up really well and they are in the Asian Champions League."
Coyne played his last match for Perth on January 7 before being unceremoniously frozen out of the first team.