What muscle is this?

Winter conditioning officially starts tomorrow! Yay!

I’ve been doing some extra workouts at home to get even more prepared for this upcoming season. Looking back to last season I remember a slight soreness in my upper left arm (throwing arm) and I’m not really sure which muscle or tendon is causing this slight discomfort. Its on the outside of my arm and runs at about a 45 degree angle between my bicep and tricep. My best guess after a little internet research is the Brachialis, but I’m not entirely sure.

Anybody have suggestions on what muscle it is and how I can strengthen it?

Besides the rotator cuff, ur upper arm has biceps, brachial radialus, and tricep. U probably have some bicep soreness from deceleration of the arm after release. Very common.

Has and exercise for this. Or you can throw a ball backwards in the same fashion , against a wall for easy retrieval.