Elbow Pain

I’m a D2 pitcher going into my junior year. My elbow has been hurting me and the pain comes back even after returning from rest. The Doctor told me it was my MCL and most players play their entire career with partially torn MCLs but if the pain kept up i should get the surgery. The doctor was an old doctor for the Mets so trust his opinion. Does anyone know anything i can do to strengthen my elbow so that i don’t have to get Tommy John surgery?