During what season of Europe's secondary club football tournament was the  2017 UEFA Europa League Final, where Manchester United finished in sixth place?
2016–17 Manchester United F.C. season:  Although they missed out on qualifying for the 2017–18 UEFA Champions League via the league, having finished in sixth place, a 2–0 victory over Ajax in the 2017 UEFA Europa League Final meant they qualified for the Champions League group stage as Europa League title holders.
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