By Neil Ashton PUBLISHED: 14:46 EST, 11 March 2014 | UPDATED: 20:35 EST, 11 March 2014 Arsene Wenger suffered massive embarrassment in the Allianz Arena when he could only name six substitutes against Bayern Munich because of an administrative error. Ryo Miyaichi flew out with the Arsenal team for the clash but it was later discovered that he is not registered in Arsenalâ€™s Champions League squad. In action: Miyaichi training at London Colney on Tuesday ahead of the second leg Short: Arsene Wenger could only name six subs at the Allianz Arena, including youngster Isaac Hayden
@highlight
Ryo Miyaichi travelled with squad but wasn't on the six-man bench
@highlight
Arsenal thought he was registered with the Champions League squad in the B list for under 21s who have been at the club for over three years
@highlight
But with the Japanese wingers' loans in recent seasons, he has not been at the club for over three years in total
@highlight
Arsenal were therefore unable to pick Miyaichi for the second leg, which Arsene Wenger's side drew 1-1 on the night and lost 3-1 on aggregate
Experience: Youngster Isaac Hayden (right), who has made only one @placeholder appearance, was on the bench