The 17-year-old has made a major impression since his arrival from Stuttgart last summer and has recently been hailed by Arsène Wenger as “a big hope for the future”.
Gnabry is likely to feature against Coventry in the Capital One Cup third round on Wednesday night and Djourou says supporters will see a special talent.
“We have a lot of great young guys coming through and one of them is Serge Gnabry,” he told the Official Matchday Programme.
“He’s a very good young player, really tricky, and someone with a big future ahead of him. He has all the attributes to become a very good winger or No 10, and has the right character too.
“If you have that, and don’t get carried away, you have a great chance.”
Djourou captained a young Arsenal side at the same stage of last season’s League Cup against Shrewsbury, and says it was a memorable occasion for him.
“It was privilege to captain Arsenal - something special,” he said. “It showed a real respect towards me, too.
“This is a competition that I will take very seriously as a chance to, hopefully, get a game and help us through to the next round. We need to come out and give everything to win.”
You can read the full interview with Johan in the matchday programme for the Coventry match. Click here to subscribe
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Please note that Gold Season Tickets are NOT valid for Wednesday night’s Capital One Cup third-round match against Coventry CityCopyright 2016 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source