Robert Lewandowski had levelled in the second half after Louis Poznanski's own goal before Nketiah struck late on to end Arsenal's recent hoodoo against the German champions.
Pierre-Emerick Aubameyang and Alexandre Lacazette are the club's leading strikers, but the Arsenal supporters believe Nketiah has shown enough quality to be the next man in line.
Joe Willock looked comfortable in the starting line-up while Tyreece John-Jules and Bukayo Saka didn't look out of place after coming on as late substitutes.
Arsenal return to pre-season action on Saturday when they play Serie A side Fiorentina.
"Players like Hernandez and Benjamin Pavard can only help us".
"We need new signings". Against Colorado Rapids a lot of young players played. Our responsibility at this club for the history, for the present and for the future is to have young players with the possibilities to take chances. "I'm very happy with them".
Arsenal'sEddie Nketiah during the UEFA Europa League, group E match at Emirates Stadium, London.
"We want to win every match, this is not the most important but really we can see important things for us, for our ideas". For example, the attendance record of the match MCC was established in 2014 in the game between real Madrid and the English "Manchester United", which was visited in the American Ann arbor more than 109 million viewers.
Apple unveils new emoji in celebration of World Emoji Day
It's World Emoji Day and Apple has taken the opportunity to unveil some of the new emoji that it announced at WWDC last month. Since Apple is such a progressive company, it is also using emojis as a platform to further its message of equality.