Question: When does the champions league group stage start?

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question: When does the 2017-2018 champions league group stage start?
short_answers: 12 September 2017
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question: When does the 2016-2017 champions league group stage start?
short_answers: 13 September 2016
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question: When does the 2015-2016 champions league group stage start?
short_answers: 15 September 2015
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question: When did the 2017-18 UEFA Champions League group stage start?
short_answers: 12 September 2017
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question: When did the 2016-17 UEFA Champions League group stage start?
short_answers: 13 September 2016
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question: When did the 2015-16 UEFA Champions League group stage start?
short_answers: 15 September 2015

Answer: The UEFA Champions League is an annual club football competition organised by the Union of European Football Associations (UEFA) and contested by top-division European clubs, deciding the competition winners through a round robin group stage to qualify for a double-legged knockout format, and a single leg final. The 2015-16 UEFA Champions League group stage started on 15 September 2015. The 2016-2017 UEFA Champions League group stage started on 13 September 2016. The 2017-2018 UEFA Champions League group stage started on 12 September 2017.