Shoulder pain is probably something most of us experienced at this point, for me it has been a big Problem in the past and just started to return. I often have trouble hitting the Balls hard then and only after some time it Starts to resolve during playing only to Return again after i stopped.
It most likely is due to an incorrect technique and a too short warm up in this area. I often stand beside a Wall and try to train the right way of hitting the ball as it should be straight from above and not from the side, which would probably cause the pain.
Do some of you have good warmup routine for that shoulder area or other exercises? Any tips help!