article_snippet: The midfielder-cum-defender put in a weak challenge and allowed Alex Oxlade-Chamberlain to set up Nacho Monreal for Arsenal's first before playing a poor backpass to set up Danny Welbeck for The midfielder-cum-defender second-half winner.
article_snippet: The midfielder-cum-defender inexplicably let Danny Welbeck in for his second-half winner with an awful backpass .
article_snippet: Nacho Monreal (left) scored Arsenal's first, with Antonia Valencia involved in the defensive collpase .
article_snippet: Tomorrow is another day and keep working,' Nacho Monreal (left) added before tagging team-mates Marcos Rojo, Juan Mata, Ander Herrera, Rafael and Robin van Persie in the message.
highlights_snippet: Manchester United's defeat by Arsenal .
  
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