Germany head coach Joachim Low believes his experimental side must find an extra gear to get past Chile in their next Confederations Cup match.
The world champions began with a 3-2 victory over Australia in Sochi on Monday, where Lars Stindl and Leon Goretzka netted their maiden international goals either side of a converted penalty from captain and man-of-the-match Julian Draxler.
A pair of errors by goalkeeper Bernd Leno allowed Tom Rogic and Tomi Juric to pull Australia back into the contest when Die Mannschaft should have been out of sight by weight of first-half opportunities alone.
Low rested many of his leading stars for the tournament and, although his youth and fringe players sparkled for the first hour, they closed the show nervously as Australia sniffed an equaliser.
The 57-year-old warned Copa America holders Chile will be a different proposition entirely after opening Group B with a win of their own, 2-0 against Cameroon in Kazan.
"Chile is going to be a match on an entirely different level because Chile is playing with great intensity and ability," Low said at his post-match news conference. "We must retain our stability over 90 minutes, not 60.
"In the first half we played very well, good combinations and everything was under control. The bad thing of it all was we had only a 2-1 lead. We had a number of other opportunities.
"We were unable to score a third or a fourth. Australia didn't really have any opportunities other than their goal.
"In the second half, after 60 minutes, we lost our common thread and our attacks were not so consistent. We need to work on that to retain our stability.
"But with a new team I think things have worked very well. I don't think you should have excessively high expectations. There were good approaches by my team."
Germany's tactical flexibility during the first half, with Draxler roving in from the left flank as Julian Brandt caused havoc down the right and the midfielders inside interchanged with aplomb, was a delight to behold at Fisht Stadium.
Nevertheless, Low was keen to warn that Chile are also masterful in this department.
"Chile are one of the world's best teams, no matter what you say about this tournament," he said. "Chile are well experienced and have fantastic individual players. In terms of tactics they are as flexible as any other team.
"They can change things as matches are still going. It's amazing to see how they are playing. Every tournament has different dynamics."
Schalke midfielder Goretzka was involved in the build-up to Stindl's fifth-minute opener and was clattered by Massimo Luongo to win Germany's penalty before enjoying his own moment of glory, leaving the coach suitably impressed.
"He was very strong," Low added. "In the past days he has been involved in our activities and this match has shown he is a very present personality.
"He has won one-on-ones and he is running from the midfield deep into the area and that is very hard to fight back from for the opponents. He has made a very good impression."