Alex Iwobi opened scoring only for his Arsenal to lose 3-1 at French Ligue 1 club Rennes in the UEFA Europa League.
The Nigeria international scored as early as the third minute only for the home team to fight back and win 3-1 after Arsenal were reduced to 10 men before half time.
Iwobi will then be replaced in the 53rd minute.
The London Gunners will now hope to turn the table in the return leg next week.