Arsenal will face tournament favourites Atletico Madrid over two legs for a place in the final of the Europa League.
The Gunners survived a scare to eventually beat CSKA Moscow 6-3 on aggregate in the quarter-finals and will now take on Atleti in the toughest possible semi-final draw.
Atleti, who edged past Sporting Lisbon 2-1, are to travel to the Emirates Stadium on April 26 for the first ever competitive meeting between the two clubs, before welcoming Arsenal to the Spanish capital a week later.
The winners of that intriguing tie will take on either Marseille or Red Bull Salzburg in the final, with those two sides being drawn out of the hat first in Friday morning's draw.
Marseille and Salzburg came through dramatic second-leg fixtures on Thursday, both overcoming big deficits to remain on course for a place in next month's final, which will be held at Olympique Parc Lyonnais.
Germany
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Hungary
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Spain
Italy
Croatia
Albania
England
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Slovenia
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