Arsenal are set to face Manchester United in a crucial Premier League clash at Old Trafford, but there are now some injury concerns. The Gunners were enjoying having an entirely fit squad for the first time since 2019 following the return of Jurrien Timber, but they may now be without some key players yet again. Takehiro Tomiyasu missed a training session earlier this week, whilst there have been constant questions over the fitness of Bukayo Saka after some heavy challenges, including a reckless one from Bournemouth midfielder Ryan Christie in the last game. It now appears that Arsenal are swe…