Atleti's Luciano Vietto broke the deadlock at National Stadium with a headed goal from an Angel Correa cross four minutes before half-time, but the lead lasted just two second-half minutes thanks to a superb Emile Smith Rowe effort for the Gunners.
The win means Atletico now occupies the 7th position on the log with 3 points from one game, while the Gunners occupies the 9th position with no point from one game.
'For the history of Arsenal, it needs every year and every day for us to work with young players to give them the chance to work for us and show their quality.
Unai Emery has challenged the rest of Arsenal's young players to follow the example set by Emile Smith Rowe.
Emery was appointed as Arsenal head coach in May
Arsenal were on top for most of the game as their Spanish opponents were without the likes of Antoine Griezmann, Diego Godin and Diego Costa.
"It is always nice to play with your old team-mates, with Aubameyang and Sokratis." said the midfielder.
Under International Champions Cup rules, the game went straight to penalties where substitute Atletico goalkeeper Antonio Adan starred, saving three before coolly slotting the victor himself.
Arsenal goalkeeper Petr Cech feels reassurances over his future would help Ramsey to focus on finding his best form in 2018-19, and named the Wales worldwide as one of the club's best players. For Smith Rowe to score is very good for him and the team. "We were taking on Arsenal, with the quality of their players, it is not easy and we competed well". I'm very happy with his work on the pitch but it's not only today, it's every day.
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