Chances are you are looking at this post because you have a tie to baseball. From here on out, I'm going to speak to you as if you are the player. I am a college baseball player who is in the same position as millions of ball players everywhere- trying to get stronger for the upcoming season. Does this sound like you? Here's a good starting point; throw out that workout your coach gave to the whole team. Ask yourself these two questions 1. Is this workout just trying to make me stronger or is it helping me becoming a better ballplayer? and 2. Am I training the muscles I will be using or the movements I use in the season? If your program is following the first option for each question, it is time to make changes. There is very little benefit from cookie cutter baseball workout with arm days and leg days. When was the last time you did anything in baseball that did not require your whole body to work together? Full body workouts not only have a greater return for baseball players, but also allow you to require less days in the gym.
You are probably working exclusively on a sagital plane.
In layman's terms, this means you are only working in an up and down fashion. None of your drills work on rotational power, or lateral movement. The best exercises you can do are ones that closest emulate baseball- specific motions. Shoulder presses not only restrict scapular movement, but they also do not include any athletic motion that you use in baseball. I am a huge fan of rotational med balls slams and any variation of the drill. If you don't know what these are, here is Atlanta Braves prospect Chad Rogers doing a med ball drill at Cressey Performance in Hudson, MA. Cressey Performance is viewed as the gold standard for baseball strength training, so they know a thing or two about what they are doing.
Notice how this drill works on baseball specific movements. This is the key to a successful workout program. Stop focusing on the muscles that baseball players use, and start focusing on the compound movements that have a direct effect on your baseball career.