Nike Jr. Mercurial Juniors Indoor Football Trainers The Nike Jr. Mercurial Juniors Indoor Football Trainers are perfect for training and matches, designed with a low profile ankle collar coupled with a lace fastening that helps to lock your foot down into the shoe for a secure feel, while the cushioned insole and midsole gives a responsive feel. A moulded outsole and multi directional tread pattern ensures grip for sudden turns and stops, finished off with the Nike branding to the side.