"He will be involved," said Mackay of the 22 year old midfielder.
"I am delighted to finally get him here, it has been quite a long and drawn out saga, with Korea, Japan and the Olympics mixed in all that," said Mackay.
"It has been going on for quite a while because I watched him against Spain before the Euros and it has gone on from there.
"He had to go back to Korea to be with the Olympic team and they got a bronze medal and went right to the end of the tournament.
"We had administration and paperwork to do in Korea and I had to go and speak to the work permit people to get him that as well.
"It has been long and drawn out but he is here and I am desperately hoping we can get him involved on Sunday."