Manager Jose Mourinho has been handed a touchline ban for Sunday's Premier League game at Swansea after accepting two Football Association misconduct charges
The Portuguese coach will have been left less than impressed by the manner of his team's defeat in Istanbul.
The Turkish side took the lead inside two minutes with a brilliant overhead kick from Moussa Sow, before United saw world record signing Paul Pogba hobble off injured.
Jeremain Lens curled in a free-kick on the hour to double Fenerbahce's lead, with United captain Wayne Rooney scoring a late consolation
Following Feyenoord's 1-1 draw at Zarya Lugansk, where they finished with 10 men, United are now third in the table, a point behind leaders Fenerbahce and the Dutch side
United next host Feyenoord on November 24 and will end their Group A campaign away to Ukrainian side Zarya.
Elsewhere in Thursday's early evening kick-offs, League of Ireland champions Dundalk were beaten 2-1 away at Group D leaders Zenit St Petersburg.
Giuliano had put the Russians in front on 41 minutes, but Daryl Horgan's goal - following a swift counter-attack - levelled matters on 52 minutes
Zenit, though, maintained their 100 per cent record when Brazilian Giuliano netted again with 22 minutes left
The game between Maccabi Tel-Aviv and AZ Alkmaar ended goalless, meaning Dundalk retain second place in the table
Aritz Aduriz scored all the goals as Athletic Bilbao beat Genk 5-3 to open up the qualification race in Group F, the striker completing his impressive haul in stoppage time with what was a hat-rick of penalties
Sassuolo remain top after they drew 2-2 at home against Rapid Vienna, who scored a late equaliser - but no w all four teams are separated by just one point
Roma won 4-2 at Austria Vienna with a brace from Edin Dzeko to climb to the top of Group E, with the other tie ending 1-1 between A stra Giurgiu and Viktoria Plzen
Apoel Nicosia lead Group B after the Cypriots beat Swiss side Young Boys 1-0 and Olympiakos drew 1-1 away to FC Astana.
Anderlecht thumped Mainz 6-1 in Group C, where French team St Etienne, continued their qualification push with a 2-1 win at Qabala, who have yet to register a point.
Source : PA
Source: PA