Pep Guardiola is worried about Manchester City's fixture pile up as the runaway Premier League leader also challenges in the Champions League, FA Cup and EFL Cup.
A remarkable quartet of trophies is a possibility for City this season, with Guardiola's high-flying side 13 points clear in the Premier League – an advantage which could extend to 16 following its trip to Crystal Palace Sunday.
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City is also in the last 16 of the Champions League, the EFL Cup semifinals and the third round of the FA Cup.
Guardiola, however, has concerns over City's challenge on four different title fronts.
"I am worried about that," said Guardiola. "Four competitions, I don't know if we will be able to do that.
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"The schedule - you have to be careful. I am worried because we cannot play every three days.
"We cannot play Kevin De Bruyne every three days [for] 80 minutes, 80 minutes. He needs to be refreshed to help in the last part of the season.
"I have never before been in this situation. Three competitions I have handled many times, but four never.
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"And the fourth is double games [two legs], and extra time. We are going to see how we handle that situation."
City – unbeaten in England's top flight this season – is in the midst of an 18-game winning streak in the Premier League.