Leandro Trossard scored his 12th goal of the season for Arsenal to pull them level in the tie on aggregate
The Gunners went into this last-16 second leg 1-0 down but drew level when Leandro Trossard put them ahead on the night four minutes before the interval with a smooth finish following brilliant work by captain Martin Odegaard.
A scrappy, fractious encounter failed to yield a winner even after extra time and it was Arsenal who held their nerve to go through to the last eight.
Odegaard, Kai Havertz, Bukayo Saka and Declan Rice were all on target for Arsenal as David Raya saved from Wendell and Galeno to seal victory for Mikel Arteta's side amid scenes of wild celebration.
-- Courtesy of BBC Sport