The youngster forfeited a chance to play in Europe after being called up by Vietnam to play in two upcoming friendly matches
Mac was born in Vietnam before moving to Czech Republic in 2000. His services were then courted by Sparta Prague and Mac featured occasionally for the club’s reserve team until his contract expired in 2012.
Hertha Berlin, who are currently second in the Bundesliga Two and on course to be promoted to the top division, then came calling and offered the youngster a chance to impress and earn a contract.
However, the 21-year-old pulled out from the trial at Hertha Berlin to join Vietnam’s training camp on 23 January after receiving a call-up from Vietnam to play in two friendly matches at the end of the month.
"I cancelled my tryout with Hertha Berlin to join the national team. It's a pity because I had a great week here. But for me, playing for the national team is the most important and this kind of chance doesn't come every day,” Mac told Goal.com Vietnam.
Mac also cancelled another scheduled tryout with Bundesliga Three club Hansa Rostock, but remains hopeful he will get another try in Europe after playing in the friendly matches.
"As Germany's transfer window is closed on Jan 31, I will have to seek another chance in other countries after returning from Vietnam. Playing in Europe is my top priority,” he said.
Vietnam will play Vietnamese League club Vicem Hai Phong on 26 January and Korea National LeagueHyundai Mipo Dolphin on 31 January.