However, Antoine Griezmann found an equaliser with eight minutes remaining and Arsenal must now score in Madrid next week to maintain any hope of progression through to the final.
Find out how all of the action unfolded in North London courtesy of Sports Mole's minute-by-minute updates below.
ARSENAL SUBSTITUTES: Cech, Holding, Maitland-Niles, Kolasinac, Chambers, Iwobi, Nketiah
ATLETICO MADRID SUBSTITUTES: Werner, Savic, Gabi, Vitolo, Olabe, Torres, Costa
Santi 😍 pic.twitter.com/3DICmTVQgF— Arsenal FC (@Arsenal) April 26, 2018
ARSENAL XI: Ospina; Bellerin, Mustafi, Koscielny, Monreal; Xhaka, Ramsey, Wilshere; Ozil, Welbeck, Lacazette
ATLETICO MADRID XI: Oblak; Vrsaljko, Gimenez, Godin, Lucas; Correa, Thomas, Saul, Koke; Gameiro, Griezmann
If you would like to read our on-the-whistle match report, you can do so by clicking here. Goodbye for now.