Even though the Vietnamese-Czech goalkeeper accepted the call up to the national team, he was on the bench for the UEFA Nations League's match against Scotland. The Scots won 2-1.

FIFA regulations only prohibit a player who has played in full or in part in an official match from playing for another country.

The 27-year-old could thus play for Vietnam if his naturalization process is completed and coach Park Hang-seo decides to call him up for the squad.

The Czech's next match will be on October 12.

Nguyen Minh, his father, said: "My son is a Czech national who lives and plays football here. So when he was called up for the team, he could not refuse. But Filip still wants to play for Vietnam."

He was added to the squad since all the players who took part in the match against Slovakia on September 5 and the head coach were quarantined and had to miss the match against Scotland after two support staff contracted Covid.

The Vietnam Football Federation was supposed to help Nguyen obtain citizenship, but his paperwork has kept getting delayed.

In February he said he had completed all procedures for citizenship and was awaiting official word.

In 2016 he first visited Vietnam for a trial with Thanh Hoa FC but did not get selected.

He then expressed his desire to play for Vietnam several times, professing his love for the country and hoping to be part of the national team for the World Cup 2022 qualifiers.

He plays for Slovan Liberec in the top-flight Fortuna Liga, and has been one of the best goalkeepers in the league.

In the 2018-2019 season he kept a clean sheet for 440 minutes and was voted "Best Goalkeeper" of the league.

He is currently worth $887,000 according to German transfer site Transfermakt, which estimates the worth of all professional footballers.