There are two possible reasons for chest pain after hitting the chest with a ball. The first one is a rib fracture caused by the ball hitting the chest, when the chest pain is more obvious, the pain is intense when coughing and deep breathing, sometimes you can even hear the rib rubbing sound, you should go to the hospital and take a chest X-ray to check whether there is a rib fracture, whether there is a rib misalignment, whether the lung is damaged causing a hemopneumothorax. Second, chest pain can also occur with soft tissue injury to the chest. The pain is relatively mild at this time, and it can also occur when coughing and breathing. If pain occurs, physical activity should be temporarily stopped and rest should be taken.