Mikel Arteta rotated his team for the weekend's visit of Manchester City with this game in mind, but the Spaniard witnessed his side succumb to a 1-0 defeat to the Premier League leaders on their own turf.
Here, Sports Mole rounds up all of Arsenal's injury and suspension news ahead of the second leg.
Status: Minor doubt
Type of injury: Hamstring
Possible return date: February 25 (vs. Benfica)
Thomas Partey continues to recover from the hamstring issue he sustained against Aston Villa, and he played no part against Man City. However, the former Atletico Madrid man has been pictured with the ball at his feet in training, and a late decision over his involvement will be made before kickoff.
Type of injury: Concussion
Possible return date: February 28 (vs. Leicester City)
Rob Holding was named in the starting lineup against Man City but had to come off in the final 10 minutes due to a head injury, with David Luiz replacing him as a concussion substitute. Arteta expects the centre-back to miss "a few days" as a result, effectively ruling him out of contention for the second leg.
ARSENAL'S SUSPENSION LIST
Arsenal have no players suspended for the second leg.