Arsenal boss Arsene Wenger was satisfied with his side after the 1-0 win over Wolfsburg on Sunday afternoon.
The narrow win allowed the Gunners to lift the Emirates Cup for the first time since 2010 as their perfect pre-season campaign came to an end.
They will face Chelsea next Sunday as they will aim to retain the FA Community Shield at Wembley.
"It was maybe less spectacular than yesterday because we had a big problem starting and getting going," Wenger told reporters.
"But overall it was a good performance where our technical level was good, our passing was good, maybe our final ball and finishing was not top sometimes.
"In the second half we defended higher and gave them many more problems than in the first where we defended a bit too deep. Overall we had two good days.
"He [Jeff Reine-Adelaide] is 17 years old and he looks very promising but he needs to work with us for a year in the first team.
"To be an adult, to play for the under-21s and to develop. There is fantastic potential there but he will stay with us.
"I honestly don't know [how much he will play this season].
"But today was a good opportunity to see him. In some situations of course, he has the game of a 17-year-old player but on the other hand he has shown great potential as well and looks very advanced physically for his age, and I'm sure he has learned a lot these last two days.
"He [Petr Cech] has top-level experience and he is a good communicator. He brings a sort of calmness as well in the way he responds the situation but he helped to lift the confidence of our defenders."