Angel Di Maria (left) replaced Juan Mata during Manchester United's victory against Manchester City
Football's global players' union FIFPro is backing the idea of allowing a fourth substitute in games.
The International Football Association Board, the sport's rule-making body, have twice
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to allow an additional substitute in extra time of knockout matches.
But they have requested that more research be carried out on the idea.
In a FIFPro poll of players across all continents, 84% supported the idea of a fourth substitute in some form.
"The response to our survey is overwhelming," said FIFPro general-secretary Theo van Seggelen.
"Whether only applied to extra time or during the regulation 90 minutes, professional footballers worldwide surveyed by FIFPro see a need to add a fourth substitute.
"It's a position that will challenge traditional views, but the players have one of the most important roles in this debate."
Fifpro selected a representative sample of players from 27 countries and gave them the choice of three answers.
Out of 244 responses, 39 players (16%) said they were totally against a fourth substitution.
Of the remainder, 119 players (49%) were in favour of a fourth substitute but said the additional change should only be allowed in extra time. A total of 86 players (35%) were in favour of a fourth substitution even in matches of 90 minutes.
"Our research is representative of players on all continents and they have clearly shown a preference for the game to evolve and show greater flexibility, especially during matches that go to extra time," said Van Seggelen.