Arsenal coaches were left amazed by Reuell Walters in training ahead of the clash against PSV tonight. In a video posted on Arsenal’s official website, Mikel Arteta was putting his players through their paces ahead of their last game in the group stages of the Champions League. The Gunners have booked a place in the knockout stages after topping their group and Arteta is expected to make several changes in the Netherlands on Tuesday evening. Indeed, Reuell Walters is reportedly pushing for his Arsenal debut while Ethan Nwaneri has also travelled with the squad. Walters is expected to get an op…