I'm just curious if anyone else has had a soreness between the thumb and the index finger from playing a lot of tennis. I use the PDRGT which is notorious for damage peoples shoulders/arm.. however i havnt had that problem. My problem is in the gripping of the racquet and sometimes when I miss hit it sends those vibrations into my hand.. after a set or 2 it starts to hurt. It's kind of like bowling for a long time, eventually your hand hurts to grip onto things. I'm a 3.5 player, 23 yrs old.