Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Manchester United right back Matteo Darmian has gone 'off the boil' according to club legend Denis Irwin after a promising start in English football. The 25-year-old, a £12.7million summer signing from Torino, impressed during pre-season and was voted United's player of the month for August. However, the Italy international has since experienced a dip in his form and was at fault for both of PSV's goals in the Red Devils' 2-1 Champions League defeat in September, as well as substituted at half-time in their 3-0 Premier League loss to Arsenal. Irwin, who was part of United's famous treble-winning side in 1999, believes that a lull was was inevitable and that Darmian is simply succumbing to the pressures of his new surroundings.Matteo Darmian signed for Manchester United in the summerThe 25-year-old Italian cost a reported £12.7m fee from TorinoDarmian impressed with his early performances in EnglandHe has since experienced a dip in his formUnited legend Denis Irwin says Darmian's lull is to be expected when adjusting to the demands of a new league 
 Question:A foot injury to Antonio Valencia leaves _ as United's only available experienced right back at present.

Matteo Darmian