In the 67th minute Koscielny fouled Gerard Deulofeu to concede a penalty, which David Silva finished comfortably.
Then five minutes later the Arsenal centre-back clashed heads with Bayern Munich midfielder Thiago.
The stunning Arsenal XI that could've been
Sun, March 26, 2017
Express Sport brings you the stunning Arsenal XI that could've been …if Arsene Wenger had signed these superstar players
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This is an Arsenal team Arsene Wenger could've had if he'd sighed these players
The 31-year-old received treatment on the pitch and looked set to be replaced by Aymeric Laporte.
But Koscielny had strapping applied to his head and was able to remain on the pitch.
France's Laurent Koscielny receives medical attention
Moments later Deulofeu tapped home to give Spain a 2-0 lead, in a game which saw video technology used.
Antoine Griezmann scored early in the second half but the video ref ruled it out for offside.
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