Chelsea boss Thomas Tuchel has stressed on the importance of giving players adequate time to rest ahead of the new campaign.
The German boss has welcomed a series of first-team players back to training, while others are due to return following their involvement in the European Championships and Copa America in the summer.
Amid a global pandemic, the expectations on professional players were as high as ever last term, and Tuchel has erred on the fact that footballers need to be given proper time to rest and recover physically and mentally.
Asked if international tournaments affect managers' preparations ahead of a new campaign, the ex-Borussia Dortmund boss said: "Yes, and it gets more and more complicated these days, because there's almost every year a tournament," as quoted by Chelsea's official website.
"Two years ago, there was a Copa America, this year again there was a Copa America and European Championships, and now in 18 months, there will come a winter World Cup – again a new challenge, and we will try to find solutions while we are doing it.
"So, it gets more and more demanding to prepare teams for a whole season because there is a huge link between preparation and not being injured, between preparation and performance, and between input and output; you can put it as easy as that.
"If we don't allow the players to rest enough, and if we don't allow the players to have enough time for the input for a season, we struggle to see them perform at the highest level.
"This is what we want to do, we want to perform for the people who love the game. We want to perform on a high level, and it's complicated. This is not a cry for help and not an excuse, but it's reality. And this is not like the optimal."
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