If you’re a young player looking to force your way into the first-team set up, it’s always a positive sign when you receive a new shirt number. Take Kobbie Mainoo, for instance. He ended 2022/23 with number 73 but was then upgraded to 37 before shining during last summer’s pre-season tour. 12 months on, Mainoo is just about the first name on Manchester United’s team sheet. Fellow Carrington graduate Ethan Wheatley, meanwhile, made his senior debut against Sheffield United in the spring with 84 on his back. Now, the prolific centre-forward dons 36. Left-back Harry Amass, meanwhile, has gone fro…