"Go to bat for" is a phrase that refers to supporting or defending someone. There are several synonyms that can be used in place of this phrase, such as "champion," "advocate," and "defend." "Champion" suggests a strong support for someone, while "advocate" implies actively speaking on their behalf. "Defend" suggests protecting someone against attack or criticism. Other synonyms include "back up," "stand by," "fight for," and "stand up for." No matter which synonym is used, the important thing is to show loyalty and support for the person you are defending.