Germany's players have very different fitness levels ahead of their Nations League opener against Spain on Thursday and will struggle to last 90 minutes due to the fragmented end to the previous season across Europe, coach Joachim Loew said.
The Germans return to international action almost 10 months since their last match as the Covid-19 pandemic interrupted the global sports calendar.
"The situation that we have here is that there are a lot of differences between players," Loew told a news conference.
"Some have been training for some weeks but have no match practice. Others just finished playing in the Champions League and the Europa League.
"Others are just back from holidays that were short. I don't think players will last over 90 minutes at a high pace."
Germany, who also play Switzerland in the Nations League on Sept. 6, are looking ahead to next year's European championship and Loew said it would take longer than usual to have a fine-tuned tournament team ready.
"The overriding goal is next year's tournament. This year we will not be playing with an identical team any time soon," Loew said.
Germany will be largely deprived of players from Champions League winners Bayern Munich and semi-finalists RB Leipzig.
All Bayern and Leipzig players have been rested for the two games, with the exception of Bayern's Niklas Suele, who only returned from a lengthy injury break at the end of the season, and Leroy Sane, who joined the German champions from Manchester City in the close season.
Barcelona's Marc-Andre ter Stegen, Germany's second-choice keeper, has also been rested.
"We will not be able to start fine-tuning the team before next March, the final pre-tournament friendlies and the training camp," Loew said. "What is important is to overcome this difficult and busy season and arrive fresh at the tournament next year."
"We saw at the Champions League tournament how important that freshness was," Loew said.