Arm soreness is as much as part of baseball and softball as pine tar and rosin bags, but that doesn't mean coaches should ignore a player who seems to be struggling with a tired wing.
In 2010, Washington Nationals phenom pitcher Stephen Strasburg felt some soreness in his right shoulder and cautiously, the team put him on the disabled list for the first time in his career. During his third start back from the DL, he felt an excruciating pain shoot through his throwing arm as a ligament in his elbow snapped, which required Tommy John surgery to repair the injury.
When pitchers throw with a sore arm, they're oftentimes compensating for the soreness by utilizing different muscles and ligaments. As one of the best pitching prospects in the past decade, Strasburg likely played through a lot of soreness that fatigued certain parts of his arm and eventually caught up with him.
Pitchers and position players alike, especially those who are very young, should always stretch their arms well before taking the field. During the games, coaches should be sure to provide an ample supply of water for their players. When muscles aren't fueled by enough water, they are stressed and become susceptible to strains and tears. Players should do their best to keep their arms loose and warm throughout games, which they can do with arm sleeves or compression undershirts.
After every game, players who used their arms extensively – most commonly pitchers and catchers – should apply a cold pack to reduce muscle swelling and pain. Additionally, it's important that players rest their arms until the soreness subsides and do not try to overwork them.