Manchester United will need a result on matchday six away at Leipzig after succumbing to a 3-1 defeat by Paris Saint-Germain.
Brazil star Neymar started and finished the scoring for the French side, who matched RB Leipzig's result at Istanbul Basaksehir to leave three teams on nine points in Group H.
United equalised through a Danilo Pereira own goal but then suffered a double blow in the second half when Marquinhos poked home for the visitors before Fred was sent off for a second yellow card, having escaped a red in the first half for a headbutt on Leandro Paredes.