Dominick Cruz Says Cody Garbrandt Is Dumb As Hell

The barrage of smack talk between UFC fighters Cody Garbrandt and Dominick Cruz continues ... with Cruz telling TMZ Sports the only thing emptier than Cody's threats are his head ... 'cause he's dumb.

These two are scheduled to meet up at UFC 207 December 30th ... and have been destroying each other in the media, with the most recent shot coming from Garbrandt about Cruz's new beard.

Well, Cruz checked in with the guys on the "TMZ Sports" TV show ... and UNLOADED on Cody ... saying his insults are coming from a very small place ... his brain.

Be sure to watch "TMZ Sports" weeknights on FS1.