A recent change in Fifa rules has made it easier for players to switch national team allegiances and there will be some players heading to the World Cup in Qatar who have represented other nations in the past.
At the 70th Fifa Congress in September 2020, a rule change was made that now allows players to switch nationalities if they have played no more than three competitive matches at senior level prior to them turning 21, including no appearances in Fifa World Cup finals matches or continental finals.
There will be a couple of African examples of that in Qatar, as well as several players who turned out for the junior national teams of one country and have gone on to play senior football for another. We pick five of the most prominent examples.
MUNIR EL HADDADI (MOROCCO)
The striker was born and raised in Spain, coming through the famed Barcelona academy and making his senior debut for the Catalan giants in 2014.
He had been a star of the Spanish junior national teams, scoring goals for fun, and was handed a first senior cap also in 2014 aged 19, playing 13 minutes in a 5-1 win over Macedonia.
That was likely to tie him down to Spain as Morocco made overtures, as the rules at the time stated he could not then switch allegiances.
His career path has not quite gone as he had hoped and in the years since he had spells on loan at Valencia and Alaves, moved to Sevilla and then joined Getafe this season.
He was not capped again by Spain, and as far back as 2017 he requested to be able to switch allegiances to Morocco in order to play in the 2018 World Cup.
This was denied, but once the latest rule change came into force he was able to debut for the Atlas Lions, which he did against Mauritania in March 2021.
He has not exactly set the world alight with Morocco, but is expected to be part of their squad that travels to Qatar.
INAKI WILLIAMS (GHANA)
Williams was also born in Spain to Ghanian parents and grew up in Bilbao, joining the youth academy at Athletic in 2012.
He made his senior debut for the side in 2014 and has mostly been a regular ever since, astonishingly featuring in every LaLiga match for Athletic since the start of the 2016-17 season. That is a run of 241 successive games!
The pacy forward was a junior international with Spain and handed his senior debut against Bosnia-Herzegovina in 2016, again seemingly a move just to keep him in the locker for the European country should they feel they need him in the future.
He also featured for the Basque representative side in 2018, a team from the region of Spain that many who live there see as a separate country.
Williams initially turned down overtures from Spain, but as things fizzled out with Spain, he warmed to the idea and in July this year he publicly stated he wanted to play for the Black Stars.
The change in rule meant he could, and he debuted for the side against Brazil in September.
KALIDOU KOULIBALY (SENEGAL)
Koulibaly never played a senior game for France, but played for the country of his birth at junior international level before deciding at the relatively late age of 24 to start playing for Senegal.
The centre-back was born in Saint-Dié-des-Vosges and started his professional career with Metz, winning caps for France at Under-20 level, including at the World Cup in 2011.
He was courted by French coach Didier Deschamps, but in 2015 decided to play for Senegal, and has been a regular ever since.
He will be a key figure for the team in Qatar, having recently moved to Chelsea after sight successful years with Napoli in Serie A.
ERIC MAXIM CHOUPO-MOTING (CAMEROON)
The Bayern Munich forward was born in Hamburg and played for Germany at both Under-19 and Under-21 level, but very shortly afterwards decided to play for the Cameroon national side.
He has a German mother and Cameroonian father, and played for the land of his birth at the junior Euros before the lure of a promised place in the Indomitable Lions team at the 2010 World Cup in South Africa was too great.
He also featured for the team at the 2014 World Cup, having been the subject of a complaint by Tunisia, who believed he was not eligible. This was some four years after he had made his debut and came as the two countries sparred in World Cup qualification.
Fifa cleared the player though and Choupo-Moting has been a more or less regular feature for Cameroon, though there were times when he opted out of playing for the national side, including at the 2017 Africa Cup of Nations finals.
HAKIM ZIYECH (MOROCCO)
Ziyech was born in the Netherlands and featured for them at both Under-20 and Under-21 level but made the switch to the Morocco senior national side in 2015.
The Chelsea playmaker is only just back after a self-imposed exile following a falling out with former Morocco coach Vahid Halihodzic, who had accused him of feigning injury to get out of a national team call-up.
Ziyech played for Heerenveen and FC Twente before joining Ajax Amsterdam in 2016. He was already a Moroccan international by then, having debuted against the Ivory Coast the year earlier.
His peak in the national team was 2018 and 2019, but he will be a key figure in Qatar with his experience and x-factor that makes him a dangerous opponent, even if he has been used sparingly by Chelsea this campaign.