The Scottish manager cut a forlorn figure as the Afro-haired Belgian was ordered off the pitch for an accumulation of niggling fouls throughout the night.
Moyes hinted the Anoeta Stadium crowd may have had a part to play in his midfielder’s eventual dismissal during an interview with ITV, as reported by ESPN:
It was the totting up [of tackles] that got him [Fellaini] sent off but I thought it was harsh. I thought there were some strange decisions all night. The crowd whistled an awful lot for things tonight.
We had enough chances to win it, we controlled it for most of the game. It was there to take, to get into a strong position or even get clear in the group and we should have taken three points.
Fellaini’s red card summed up a frustrating night for last season's Premier League winners.
This was United’s chance to all but confirm a place in the Champions League Round of 16 and an opportunity to state their intention against a La Liga side who loitered on zero points before the 0-0 draw.
Instead, United strikers Robin van Persie and Javier Hernandez grabbed headlines by missing a trio of simple chances in front of Claudio Bravo’s goal.
Van Persie saw his 70th-minute penalty crash off the keeper’s post after replacing Wayne Rooney just seven minutes beforehand, while he was also responsible for hitting an upright from a decent angle when Bravo’s net was gaping.
Hernandez’s failure outweighed both of these chances. The Mexican poacher, who continues to struggle for first-team opportunities, blazed a fine Shinji Kagawa ball over from five yards before being substituted for Ashley Young.
His replacement added to United's woes by contributing another alleged dive to his collection with a timid flop to win Van Persie’s penalty.
Moyes’ frustration was visible on the sidelines as the match progressed, especially considering his side asserted so much control.
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Fellaini broke up play well with a tidy performance, but every failed challenge appeared to include elbows, knees or a barge.
As such, United will travel to Bayer Leverkusen without the former Everton man on Nov. 27. The English side remain in control of Group A and are currently one point ahead of their upcoming German opponents.
A win in the BayArena would confirm qualification for Moyes’ men with a game to spare.