LW- Yannick Carrasco
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Yannick Carrasco has blown hot & cold throughout his professional career. He was an exciting talent at Genk and AS Monaco but things have not been all rosy at Atletico Madrid. While he has scored in a Champions League final, he also left for China in 2018 before returning to the Spanish club 18 months later.
Regardless, his performances for Belgium have rarely dithered. Despite several managers opting for a 3-4-3 formation with the Red Devils, they have all found a way to incorporate Carrasco into their squad.
He has often played as a left-wing back, due to the amount of quality in the traditional winger role. But he has performed those duties impeccably.
The winger also had the chance to represent Spain after gaining citizenship a couple of years after joining Atletico.
However, being born and brought up in Belgium, coupled with opportunities in the national team, Carrasco was only going to play for one country. Spain do currently have their own bunch of talented wingers, hence, they might not consider the 28-year-old ace's decision all that big a blow.
RW- Lionel Messi
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Spain's biggest ever regret could be not managing to convince Lionel Messi to join the national setup when they had the chance. After relocating to the country to progress in his career with Barcelona, the seven-time Ballon d'Or winner could have represented either Argentina or Spain. It is important to note that the player's grandfather was born in Balaguer, Spain.
Barcelona's director of football, Carlos Rexach, also pushed the Spanish Federation to secure the future of the player. But the legendary forward opted against it as he wanted to play for the country he and his family hailed from.
Since making that decision, Messi has shed sweat and tears to win a trophy with Argentina. It would have been hard for him to see some of his club teammates lift the European Championship twice and the World Cup.
However, last year, the sensational attacker led his country to glory in the Copa America. It was a competition he narrowly missed out on twice before eventually winning it.
Spain could have flourished with Messi and gone on to win more silverware. But few would argue with the four-time Champions League winner about his decision to stay with Argentina.
ST- Angel Correa
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Although not the most formidable name on the list, Angel Correa is certainly somebody Spain could have done with in their national team. The centre-forward joined Atletico Madrid in 2015 and gained Spanish citizenship a few years later.
But like Messi, Correa chose to play for his home country, Argentina. The 26-year-old ace performed well at youth level for the South American nation and also earned his first senior cap in 2015. However, he has only made 19 appearances since then and could be regretting his decision of opting against representing Spain.
La Roja have not had a decent striker since David Villa and Fernando Torres. Alvaro Morata has not been able to establish himself completely while Dani Olmo is the next hope for the country.
Correa is a fine talent and could have added quality to the ranks of the Spanish national team. But playing for your native land has its own pride and the centre-forward might be content with that.