Following the conclusion of the draw on Monday afternoon, Barcelona and Manchester United will face off in the Europa League knockout round play-offs.
Barcelona failed to advance from the Champions League group stage and will play in the Europa League for the second season in a row. Meanwhile, United finished second in their Europa League group.
The last time these two clubs met was in the Champions League quarterfinals in 2018-19. Overall, Barcelona won 4-0.
They have met twice in the Champions League finals and once in the Cup Winners' Cup final in 1991, but this will be their first meeting in the Europa League.
The winners of the eight knockout round play-off games will advance to the last 16. The eight Europa League group winners advanced automatically to the last 16.
After exiting Europe's top club competition, Juventus will face French club Nantes in a rematch of the 1996 Champions League semi-final, which the Italians won.
PSV Eindhoven will play Sevilla. Six times, Sevilla has won the Europa League or its predecessor, the UEFA Cup.
Union Berlin, the Bundesliga's top team, will face Ajax, while Shakhtar Donetsk of Ukraine will face Rennes of France.
Red Bull Salzburg will face Jose Mourinho's Roma, while Bayer Leverkusen will face Monaco.
Arsenal, Real Betis, Union Saint-Gilloise of Belgium, Real Sociedad, Feyenoord, Freiburg, and Ferencvaros have all already advanced to the round of 16.
This season's Europa League final will be held in Budapest on May 31, 2019.
Draw for the Europa League knockout round play-offs:
Manchester United (ENG) vs. Barcelona (ESP)
Nantes (FRA) vs. Juventus (ITA)
Midtjylland (DEN) vs. Sporting (POR)
Rennes (FRA) vs. Shakhtar Donetsk (UKR)
Union Berlin (GER) vs. Ajax (NED)
Monaco (FRA) vs. Bayer Leverkusen (GER)
PSV Eindhoven (NED) vs. Sevilla (ESP)
Roma vs. Red Bull Salzburg (AUT) (ITA)