MLB's Bruce Maxwell Banned From Postmates After Gun Arrest

We're still waiting on Bruce Maxwell's side of the story after he allegedly pulled a gun on a female courier ... but one thing's for sure -- he ain't getting served by the same delivery company ever again.

We got in touch with Postmates after Maxwell -- the only MLB player who took a knee last season -- allegedly stuck a handgun in the face of their driver who brought him food at his Scottsdale, AZ home ... and we're told the A's catcher "has been removed from the platform."

"Although we’re still investigating the incident, the report is deeply concerning and we’ve reached out to provide assistance and support to the courier involved," a rep said in a statement.

"No one should ever feel unsafe when using our service, and we will work with the police to cooperate fully with this investigation."

TMZ Sports broke the story ... Maxwell was arrested for assault with a deadly weapon and disorderly conduct on Saturday. Cops say he reeked of booze and berated them with "anti-police statements."