The only difference is that the Champions League 16 draws 8, and the top 32 of the Europa League draws lots to decide the game first, and then draws lots to decide that the 16 game will score 8, that is, two rounds will be drawn at a time.
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This is the draw for the top 32 last season.
Then, after the Champions League and the European Union decide the quarterfinals at the same time, draw lots and the next game will come out.
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Last season's Europa League 1/4 final draw.