The stats may make nervy reading after defeat at Porto in the Champions League last 16, but Arsenal manager Mikel Arteta insists his side will "learn" before the second leg in north London.
The Gunners lost in stoppage time thanks to Galeno's superb strike but Arteta remains confident Arsenal will prevail in the tie.
Arsenal have not reached the quarter-final stage since 2009-10 and have won the first leg in just one of their last 12 two-legged knockout ties in the competition (drawing two and losing nine).
They are also competing in the Champions League for the first time since 2017 and looked far short of their free-flowing best at the Estadio do Dragao.