#4 No Aubameyang
New signing Pierre-Emerick Aubameyang was declared ineligible to be a part of Arsenal's Europa League squad for the knockout stages of the competition.
As per UEFA's rules, he was denied his place in the squad since his former team, Borussia Dortmund dropped down into the competition following their exit from the Champions League.
Aubameyang's absence and Alexandre Lacazette's injury has been a massive blow for Arsenal.
The former Dortmund man had an impressive debut against Everton and would have been a massive bonus if he had been allowed to play.
His pace and link up play with Mkhitaryan combined with his goal threat in the box would have been the ideal formula for the Gunners in this competition.