Pep Guardiola strongly criticised the Premier League's hectic festive programme, saying of the players: "We are going to kill them."
The Manchester City boss believes it is unreasonable to expect teams to play two matches in three days, with City following up Sunday's draw against Crystal Palace by beating Watford 3-1 at the Etihad on Tuesday.
Already without Gabriel Jesus after he sustained a knee injury at Selhurst Park, City must assess right-back Kyle Walker, who appeared to pick up a problem late on.
Guardiola said: "We are going to check it out. What everyone saw in the last weeks, how many injuries the players have. We are going to kill them. I think the federation have to reflect.
"Everyone is in that business for the players. The people come here to watch and enjoy the performance of the players. Here in England, we don't protect the players and that is a big mistake.
"You have to look for the quality, not the quantity. You can play every three, four or five days but not play every two days. It is not basketball, it is not tennis. The players need recovery.
"But it doesn't matter. The show must go on. I don't think anything is going to happen because the tradition is the tradition but just think a little bit about the players, please. They are artists."
It was revealed on Monday that Jesus suffered medial ligament damage but Guardiola is hopeful the Brazilian will only be sidelined for between four and six weeks.
Kevin De Bruyne was carried off at Palace but declared himself fit to start against Watford after a late fitness test.
There was a surprise appearance, meanwhile, by playmaker David Silva, who has been absent because of a family matter.
But Guardiola revealed the Spaniard could be forced to take more time off, saying: "He's free to stay or leave, it depends.
"He wants to stay because he enjoys it a lot but family is the most important thing in life. It doesn't matter if we drop a lot of points because he is not here. I will never push him. Some days he will be here, some he will be out, it depends how his family is."
After seeing their record 18-match winning run ended by Palace, Guardiola was delighted with his side's response.
Raheem Sterling put the hosts ahead inside a minute and, although they did not completely tear Watford apart, the runaway Premier League leaders cantered to victory.
Guardiola said: "Except 15 or 20 minutes in the first half when we were not good enough, we lost simple balls, they created two or three chances, but in the second half when we could be more tired and just complacency to thinking about the result, we were completely the opposite.
"We play an amazing performance, we scored a goal, we could score more. Our fans were a little bit quiet, because maybe they were freezing or maybe it's our fans, the way we express our happiness, but I think the team showed a lot of good things. It means a lot for us."
Watford boss Marco Silva was left frustrated by the way his team started the game.
"To come here to compete and to do our best to take a good result is impossible when we start the game like we started," he said.
"We didn't start the game with enough aggressiveness in our defensive organisation, we made everything too easy for City. The first minute of the match it was clear what you cannot do at this level."