hello and welcome to HCM Since you have mentioned the same, I would like to know if your son has any previous history of allergies or asthma /reactions to any food ,dust etc. And is this the first time he is experiencing this? Given that he is using new footwear, it s highly possible that he maybe allergic to the material of it or even the synthetic socks. In this case he will have to switch over to cotton lined footwear or leather and only cotton socks. Dust could also add to it. Another possibility is a fungal infection due to moisture and sweat during playing. Make sure to wear cotton, and wash regularly..keep feet and footwear clean and dry. A fungal rash generally spreads outwards in size and you may also see whitish wet skin b/w the toes. For this you can apply a clotrimazole or terbinafine cream twice daily for two weeks and dust with candid powder. If its very red and continues to spread he will need a course of steroid cream such as mometasone furoate lightly applied only on rashes for ten to fifteen days and reduced. Do not apply for more time. Consult a doctor if it persists. Take an antihistamine like atarax or levocet every night for the itching. Allergies maybe recurrent and usually reduce with age. Keep in mind a possibility of psoriasis of the feet which maybe a later option.