Cristiano Ronaldo's abrupt and contentious exit from the Portugal national team this week has created a ripple effect within the Selecao squad.

The 41-year-old superstar, who has made the most appearances of any player in international football history, and scored the most goals, stormed out of training on Wednesday and flew home, leaving the squad suddenly just one day before they got set to face Denmark in the UEFA Nations League.

Ronaldo's anger stems from a failure to appear off the bench against Norway, just the fourth time in his entire international career that he was an unused substitute for Portugal, and just the second time since the start of 2009.

Fans will notice a jarring change in the Portugal squad as they visit Denmark without CR7, as his famous No. 7 jersey has already been given away. While that may seem like a disrespectful choice to waste no time handing off the number he became so intertwined with, there's actually a reason for Portugal offering up the shirt to another player so soon.

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Why did Portugal give 7 shirt to Rafael Leao?

According to FIFA international regulations, all national teams must allocate numbers 1-23 (or however many players are in the squad during a given international break) with no gaps left in the numerical order.

Thus, Portugal were required to give away Ronaldo's No. 7 shirt as soon as he left, with the national team registering the squad for the match against Denmark following his exit.

The number was instead given to Rafael Leao. The 27-year-old wears No. 10 at AC Milan, but that number is already taken at the international level by Bruno Fernandes. Previously, Leao wore No. 17, and that number has now been filled by Fabio Silva.

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Who else has worn No. 7 for Portugal?

Before Cristiano Ronaldo, famed international star Luis Figo wore No. 7 with Portugal, who was one of Ronaldo's inspirations for wearing the number in the first place.

Other Portugal stars to wear the No. 7 shirt include Vitor Paneira, Rui Barros, and Fernando Chalana.