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2 hours later…
2:25 PM
@Martin yes, those are the most common situations I could think of. World Cups etc. have groups of 4 but they're single-rounded; I could imagine one of the countries has a competition with a playoff structure similar to this one. — Glorfindel 30 mins ago
What are some other competitions where in group stage there are 4 teams in a group and two legs are played? (And two teams advance further.)
I was able to think of Copa Libertadores and 2019 AFC Champions League.
 

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