Celta are meeting United for the first time in the semi-finals, but they have a former Red in their ranks as they look to end the English side's bid for the last UEFA trophy that eludes them.
When are the games?
First leg, Vigo: Thursday 4 May (21:05CET)
Second leg, Manchester: Thursday 11 May (21:05CET)
First European meeting
Celta's record v English sides: W5 D0 L4
United's record v Spanish sides: W12 D19 L16
Did you know?
• The UEFA Cup/UEFA Europa League is the only major trophy that Manchester United have not won.
• United's Zlatan Ibrahimović scored the winner against Celta for Ajax in a 2003/04 UEFA Champions League group stage game.
• Ibrahimović and Celta's John Guidetti are the only Swedish players left in the competition; this season's final takes place in the Swedish capital, Stockholm, on Wednesday 24 May.
• Celta have a notable Old Trafford old boy: US-born Italy striker Giuseppe Rossi was on the Red Devils' books from 2004–07, scoring once in five league games. Celta's John Guidetti will also know his way round Manchester; he was with Man. City from 2008–15.
• Celta have lost their last three matches against English teams.
• United have won two of their three European semi-finals against Spanish opposition, all in the European Cup – going on to win the trophy on both occasions.
Borja Oubiña, former Celta defender and club ambassador
Just because we're not as experienced doesn't mean we don't have a chance of going through. Lots of fans will travel to Manchester and we'll hear them there. Let's see if we can make them happy. Getting to the semis and seeing the big sides that have been eliminated along the way shows what a good job this side – a lot of whom are home grown – are doing.