After making 12 appearances for England's U20 team and four more for the U21s during his early days, he now stands at the threshold of a change.
Currently, players can only represent one of the home nations if they, their parents, or grandparents were born there. Alternatively, they may qualify if they've undergone five years of continuous education up to the age of 18 in that nation.
However, the Football Association of Wales (FAW) is looking to persuade England, Scotland, and Northern Ireland to embrace a rule change.
If approved, this switch could completely shake-up international selection forever.
The proposed idea is players over the age of 18 who have been registered with a club in one of the home nations for at least five years could be eligible to represent that country.
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FAW believe this move would bring the home nations in line with current FIFA eligibility regulations, as reported by BBC Sport.
This means that Grimes, who recently made the move from Swansea to Coventry City after a decade with the Welsh club, could soon have the chance to don the Welsh jersey.
Grimes began his football journey with Exeter before joining Swansea in 2015, where he enjoyed memorable loan spells with Blackburn Rovers, Leeds United, and Northampton Town throughout his tenure.
He has an impressive total of 322 Championship appearances under his belt, most of them from his time in Wales.
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Had this rule been in effect earlier, players like Leon Britton would have had the opportunity to proudly represent Wales, and Cardiff midfielder Joe Ralls would now be free to join Craig Bellamy's side.
However, one of the primary concerns for the FAW is the potential for Wales-qualified youngsters to move to clubs in England, Scotland, or Northern Ireland and subsequently seek to play for those nations.
Switching international allegiances has become common place in recent years.
Jack Grealish and Declan Rice both turned out for the Republic of Ireland, thanks to their Irish heritage, before switching to England.
Mason Greenwood can play for Jamaica having previously turned out for England, though was excluded from the national team and unlikely to be made available for selection soon.
He is expected to be named in Steve McClaren's squad for the first time in June, when the Reggae Boyz have two World Cup qualifiers.
Wilfried Zaha played two senior games for England before choosing the Ivory Coast.