Carrusca, who left Adelaide United at the end of last season, has been training with Warren Joyce's side at their Bundoora base.
Club captain Bruno Fornaroli announced his arrival on Friday morning.
Fornaroli tweeted a picture with his fellow South American, writing "WELCOME TO THE FAMILY!" alongside the Argentinian and Uruguayan flags.
But his tweet was hastily deleted.
City said they are interested in the three-time A-League team of the year member, but are yet to agree on a deal with the 33-year-old.
Carrusca is a free agent after leaving United after five seasons, where he helped the club win the inaugural FFA Cup in 2014 and the A-League double in 2016.
He has obtained Australian citizenship and would not take up a visa slot should he sign with another A-League club.
Last month the attacking midfielder said he was mulling over "a couple of offers" to find a new home in.