Ryan Garcia and Gervonta Davis have BADDD BLOOD, so it's shocking the star boxer told us he does NOT want Tank locked up for domestic violence ... but only 'cause Garcia can't put his hands on Davis in jail.
Remember, Davis was arrested for domestic violence last week ... days after a video appearing to show Tank grab his baby mama by the neck went viral.
Gervonta is facing up to a year behind bars, if convicted.
TMZ Sports talked to Davis' rival, Garcia about the situation .