London - Manchester City boss Pep Guardiola warned on Friday that plans to increase the World Cup to 48 teams as well the global saturation of football is going to "kill" players.
Guardiola said he wants to see rules changed to allow for up to six substitutes to be used in a game rather than the three at present as a means to prevent burn-out of top stars.
"It's just three substitutions now, why can you not make four, five or six?," said the Spaniard.
"All the players are involved more than before, the coaches can use different tactics. Less injuries, more open games. Everything would be better."
The City boss was speaking after FIFA president Gianni Infantino expressed his desire to increase the number of teams playing at the World Cup from 2026.
But he fears that such demands will push players to breaking point.
"It's not just English football, it's all around the world. Now they talk about a World Cup of 48 teams - we are going to kill the players," he said.
"FIFA will decide and we accept the decision and if we are not happy we go home. They are focusing on more and more and more - it affects the quality. I am thinking just for the players. They need to breathe, to (have a) break, to enjoy.
"This kind of thing is impossible because we are going to finish (the season), then after one week the World Cup then after three weeks we go to the pre-season, we go to China, the States, Australia.
"You play against Milan, Juventus, Madrid and you have to win, people demand you have to play good. No preparation then you come back and it's 11 months again and it's the European Cup.
"You do this for 10 or 12 years and we don't think about the players. For that reason there has to be huge squads, more money for the clubs to spend."