Manchester United were drawn against Belgian side Club Brugge in the Europa League round of 32, while Arsenal will meet Olympiakos.
United, who won the competition in 2017, finished top of their group and were top seeds for the draw, as were last season's runners-up -- which means both sides will play the first tie away from home.
United met Brugge in the 2015-16 Champions League preliminaries when Memphis Depay and Wayne Rooney inspired them a 7-1 aggregate victory.
Club Brugge manager Philippe Clement said: "Man United are a new challenge for my boys. For them the Europa League will be very important, but we are going to play our own game."
Arsenal and Olympiakos have met eight times in the Champions League, with four victories apiece. In their last match in 2015, Olivier Giroud's hat trick in Athens gave Arsenal the three-goal victory required to progress from their group.
Meanwhile, Ajax will face Getafe and Inter Milan were drawn with Ludogorets. Record holders Sevilla will meet Cluj.
First legs will take place on Feb. 20 with the return legs a week later on Feb. 27.
The Europa League final will be on on May 27 in the Polish city of Gdansk.
Europa League round of 32 draw in full
Wolves vs. Espanyol
Sporting Lisbon vs. Istanbul Basaksehir
Getafe vs. Ajax
Bayer Leverkusen vs. Porto
FC Copenhagen vs. Celtic
APOEL vs. FC Basel
Cluj vs. Sevilla
Olympiakos vs. Arsenal
AZ Alkmaar vs. LASK
Club Brugge vs. Manchester United
FC Ludogorets vs. Inter Milan
Eintracht Frankfurt vs. FC Salzburg
Shakhtar Donetsk vs. Benfica
Wolfsburg vs. Malmo
Roma vs. Gent
Rangers vs. Braga