Baker Mayfield will be hittin' dingers for a cause this weekend ... signing on to join Christian Yelich, Charlie Sheen and more in a celeb softball game to raise money for CA fire and shooting victims.
Yelich -- along with Ryan Braun, Mitch Moustakas and Jared Goff -- created the California Strong campaign in the wake of the recent tragedies. They're all from California and decided it was their duty to help out.