The 18-year-old striker is unlikely to play in England next season due to work visa requirements. Ünal would have to be granted special permission by the FA to play football in the Premier League next season.
Ünal joined City on a £2 million transfer from Süper Lig outfit Bursaspor last month.
The Turkish international joined City on tour in Australia as part of the International Championship Cup tournament squad.
Ünal has made an appearance in every friendly game for City in Australia including the 5-4 win over Roma on penalties on Tuesday. The young striker has now played two games for the Citizens with both ending in victory.
The Turkish international was recently listed in the Guardian as one of the 40 best young talents in world football.
The City wonder-kid holds the record as being the youngest player to ever score in the Süper Lig in 2013 when he netted against Galatasaray.