Of all the complexities that modern football provides, the rules for the international game have always seemed fairly cut and dry; you play for the nation you're from and that's that.
But throughout history, players have found a way to push the boundaries and forge unique paths.
From the millions of the footballers at every level around the world, only a privileged group have had the honour of representing their country - and even fewer have done it twice.
That's because, whether it be through dual nationality or family heritage, players have been permitted to switch teams thanks to an evolving rule book, especially if they've only represented a country at youth level.
Some, however, go a step further before the change of heart, like Wilfried Zaha, who now turns out for the Ivory Coast despite two caps for England - and he'll return to face the Three Lions for the first time in a friendly at Wembley on Tuesday. Zaha's kind of journey isn't a rare one, so with that in mind, here are 10 stars who have played for more than one nation.
1. Wilfried Zaha
Starting with Tuesday's talking point, Zaha played two friendlies as a late substitute in November 2012 and August 2013, and his combined 25 minutes of action hinted at a promising career in an England shirt after impressing in their youth teams.
But following a difficult spell after a big-money transfer to Manchester United, the youngster wasn't called up again before 2016, when he informed FIFA of his decision to represent Ivory Coast.
While Roy Hodgson, who gave him his Three Lions debut and would later manage him at Crystal Palace, regretted not handing him a competitive start which would've ruled him out of a switch due to FIFA regulations being relaxed on friendlies, ex-Under-21s boss Gareth Southgate tried to persuade him to stick with England.
"I remember going to a hotel, Palace were playing away, and meeting with Wilf but at that point he had made his mind up. I can understand it because he had been four years without playing," Southgate explained ahead of Tuesday's friendly.
"I remember being asked at the time and we were asked about a few different cases and I said players have to have the desire to play for England. That was slightly tweaked a bit I would say so that created a little bit of an atmosphere with Wilf and Steve Parish for a while."
So, what could've been?
"It's hard to say what his role might have been with us. Raheem [Sterling] has been a key part of our team for a long period, Jesse Lingard had done a fabulous job and at the start we had Adam Lallana, who was our player of the year for the first 18 months or so," the Three Lions boss continued.
"He's a talent, Wilf and a massive part of Palace's ability to have stayed in the league and now the progress they're making."
2. Diego Costa
Arguably the most high-profile change of the bunch, Costa made headlines on the eve of the 2014 World Cup by ditching Brazil - hosting the tournament for the second time - for world champions and back-to-back European conquerers Spain.
After breaking into Luiz Filipe Scolari's squad in March 2013, the fearsome striker - then playing for Atletico Madrid - would play for La Roja less than a year later.
Granted Spanish nationality in July 2013, Brazil-born Costa was in the same predicament as Zaha in that he'd only played friendlies for the Selecao, allowing him to commit his international future to Spain.
Following his decision, Scolari was furious, declaring: "A Brazilian player who refuses to wear the shirt of the Brazilian national team and compete in a World Cup in your country is automatically withdrawn.
"He is turning his back on a dream of millions, to represent our national team, the five-time champions in a World Cup in Brazil." Brazilian FA judicial director Carlos Eugenio Lopes added: "It's obvious that the reason he made that choice was financial."
But Costa's Spain career was ultimately a dud, as Brazil generally fared better than Spain, beginning with a humiliating group-stage exit at that same World Cup the ex-Chelsea star rocked ahead of kick-off. Only 24 caps later, it's fair to say his international career was a shadow of his club one.
3. Alfredo Di Stefano
When it comes to legendary names in football, they don't much bigger than Di Stefano. The Real Madrid icon, nicknamed the "silver arrow" thanks to his hair colour, made his club side into potentially the greatest team football has ever seen, as Los Blancos won five successive European Cups from 1956 to 1960, all of which he scored in.
And Di Stefano almost played for as many national teams, three in fact - Argentina, Colombia and and Spain, his most memorable. Selected by the Spanish Royal Football Federation as the golden player upon their 100th anniversary in 2003, he first represented Argentina, the country of his birthday, at the 1947 Copa America aged 21.
And despite not having a passport, four unofficial friendly appearances for Colombia came afterwards, ruling him out of ever returning to play for La Albicelesta or another team as FIFA took issue with Di Stefano's fluidity, although they eventual wilted when the Spanish FA pleaded with them.
4. Ferenc Puskas
Speaking of Real Madrid in the 1950s, Puskas boasts the distinction of playing for not only one of the best-ever club teams, but one of the great international outfits, too.
Part of the 'Magical Magyars' who famously beat England 6-3 in 1953, the forward starred for Hungary by netting 84 goals across 85 appearances while playing for Budapest Honved domestically.
But after political turmoil in 1956, Puskas jetted off to Spain, combining with Di Stefano to form an unstoppable Los Blancos side. Having topped the goalscoring charts in La Liga four times, the Spanish national setup came calling and he represented them at the 1962 World Cup, winning three of his four caps during the tournament.
5. Dejan Stankovic
Renowned for being the only man to ever play for three different countries at three different World Cups, well-rounded midfielder Stankovic was a versatile player in more than one respect.
Making his debut for Yugoslavia in 1998 and scoring two goals in a 6–1 victory over South Korea, the ex-Lazio and Inter Milan engine represented them at that year's World Cup and Euro 2000.
The Yugoslav team was then renamed Serbia and Montenegro ahead of qualifying for the 2006 World Cup, a tournament which Stankovic helped them reach before losing all three of their group matches.
And after the breakup of Serbia and Montenegro that year, the current Red Star Belgrade boss was named captain of the newly-formed Serbia side.
Leading them to the 2010 World Cup in South Africa, Stankovic was instrumental in their shock 1–0 win against favourites Germany, but losses to Ghana and Australia saw them fall at the first hurdle.
Retiring from international football in 2011, he became the most-capped player in Serbia's history with 103 appearances, one more than fellow legend Savo Milosevic.
6. Declan Rice
One of the modern era's most infamous cases, London-born Rice was eligible to play for the Republic of Ireland thanks to his grandparents being from Cork.
Rising through the country's youth teams, Rice made his senior debut in March 2018, but like in Costa's case, would change his mind and don another nation's shirt within 12 months.
While Mick McCarthy told the West Ham United prodigy that he had the potential to be a future captain, his rising stock in the Premier League meant
England were interested and there was no turning back for Rice, who made his contentious decision watching the 2018 World Cup on holiday.
"Honestly, the World Cup was buzzing… I was actually in Dubai," the 23-year-old explained, having starred for the Three Lions at Euro 2020 to get an even better taste of a tournament.
"There was a massive football fan zone with a massive dome and it was crazy. It was mental. I remember watching the Panama game, the Tunisia game, the Sweden game. It was incredible.
"The singing before the game, the national anthem. Just being a part of it. I was a fan for that tournament. So, to be part of this tournament is unbelievable."
7. Ivan Rakitic
Delving into the realms of youth football, it's understandable that some players go from envisioning a career with one nation to a different one as adults.
Take Rakitic, for example, one of the finest midfielders of his generation. Born and raised in Switzerland to Croatian parents, the former Barcelona star played for five Swiss youth teams but a call-up from Croatia ahead of Euro 2008 turned his attention.
Striking a superb partnership with Luka Modric over the next decade, Rakitic helped Croatia earn the tag of Europe's perennial dark horse across five tournaments, and he was central to their historic run to the 2018 World Cup final which marked the culmination of a golden era.
8. Kalidou Koulibaly
To Africa now and one of Serie A's best centre-backs over the past decade. Having been born in France to Senegalese immigrants, Koulibaly came through the Les Bleus' youth system and was part of their squad for the under-20 World Cup in Colombia.
But despite interest from France manager Didier Deschamps, the Napoli stalwart later decided on representing Senegal.
"I don't have any regrets because I want to write the story of the future of Senegal football and I hope I'll be able to do that," Koulibaly stated when asked about his decision - and he's certainly delivered.
After becoming the first team in World Cup history to be eliminated at the group stage via a tiebreaker based on fair play, this February saw Senegal become African champions.
Captaining the Lions of Teranga, Koulibaly was a rock for Aliou Cisse's side and his leadership came to the fore in the final by scoring the first penalty after a 0-0 draw with Egypt required a shootout to decide the winner.
While France have won a World Cup and Nations League in recent years, they'll still be disappointed to have missed out on this man.
9. Pierre-Emerick Aubameyang
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Another big-name African star now in ex-Arsenal captain Aubameyang, whose solitary cap for France Under-21s allowed him to remain eligible for Gabon, who he's now the all-time top goalscorer for.
Also able to play for Spain due to endowing Spanish nationality, Aubameyang decided to represent Gabon because his father once captained the team.
As a teenager, the rapid forward was also invited to play for Italy's under-19s after an impressive season with Dijon on loan from AC Milan, meaning Aubameyang potentially could've played for three nations who've won the World Cup this century.
Instead, though, he's the hero of Gabon, helping the Panthers to their joint-best Africa Cup of Nations finish, reaching the quarter-finals in 2012.
10. Jack Grealish
Just as he was supposed to be the final piece of England's puzzle at Euro 2020, Grealish our final entry, represented the Republic of Ireland at youth level.
Unlike Rice, however, the Aston Villa academy graduate rejected a senior call-up, qualifying through his grandparents.
The switch started well, helping the Three Lions' under-21s win the Toulon tournament in 2016, but it would be four years until Southgate handed him a call-up, finally making his full England debut in a Nations League draw with Denmark.
An impact substitute at the European Championships before penalty shootout agony in the final, Grealish's international career is only getting started.
