Doug Mason -- one of Taylor Frankie Paul's suitors on her season of "The Bachelorette" -- is supporting her after TMZ published footage of her physically assaulting her ex, and the season's subsequent cancellation.

Doug hopped on Instagram Friday morning ... sharing a short clip in which he rallied behind Taylor by offering her prayers, adding ... "That was her moment and her moment was blocked."

He also told fans ... "All we can do right now is be hopeful."

You've likely seen the disturbing video we released Thursday -- Taylor is repeatedly attacking and screaming at Dakota Mortensen as her daughter cries in the background ... even throwing several bar stools at him. The incident took place in 2023 and led to her arrest for assault.

ABC pulled the plug on her season of "The Bachelorette" just hours after we posted the footage ... and Taylor spoke out saying she was grateful for ABC's support and fans will learn her side of things soon enough.

Her rep added ... "After years of silently suffering extensive mental and physical abuse as well as threats of retaliation, Taylor is finally gaining the strength to face her accuser and taking steps to ensure that she and her children are protected from any further harm."

We also told you Dakota has already taken steps to protect himself ... filing a restraining order Thursday in which he alleges a recent "chaotic" and "frightening" fight during which Taylor allegedly choked him.