My Son Is 9 Yrs Old And On A Swim

My son is 9 yrs old and on a swim meet. He swims 3 days a week. His foreskin has been itchy for a couple of weeks. I took him to his pediatrician a couple of weeks ago and his pediatrician said there is no yeast infection but maybe irritated from swimmimg. He switched to Dove sensitive skin and wears boxers and has helped slightly but the itching still comes back.