The tournament is a straight knockout format which takes place all the way until the final in Leipzig in May.
Ahead of Thursday's crucial second leg in Larnaca, here's a reminder of the crucial rules and what comes next should we progress.
How many substitutes can be used?
As with the Premier League, five substitutes are permitted per team, across the 90 minutes. However, both sides can use a sixth substitute if the tie goes to extra-time.
Is VAR in operation?
Yes. VAR will be in full operation as it will be for the rest of the competition.
Dutch official Jeroen Manschot who referees in the Eredivisie will be in charge of the VAR, assisted by Nicat Ismayilli from Azerbaijan.
Who is the referee?
Aliyar Aghayev will be the man in the middle on Thursday evening.
The 38-year-old from Azerbaijan has refereed in his home league since 2009 and has been FIFA listed since 2013.
He has strong experience in UEFA competitions, overseeing 19 UEFA Europa League matches, six UEFA Champions League games and five in the UEFA Conference League.
Fellow countrymen Zeynal Zeynalov (assistant), Akif Amirali (assistant) and Elchin Masiyev (fourth official) will help Aghayev oversee the tie.
