Arsenal star Jurrien Timber was dealt a huge blow as he picked up a long-term injury on his Premier League debut, which kept him out for the entire season. Timber returned from injury on the final day of last season, and has been building his fitness up in pre-season, with impressive performances so far on the USA tour. The Dutchman joined for £34m from Ajax last year, and is capable of performing to a very high level on both sides at fullback, and will compete with incoming signing Riccardo Calafiori for a spot at left-back. However, in his pre-season performances so far, Mikel Arteta has pla…