Matthew Morrison is taking a stand against claims he sent "flirty" text messages to a contestant on "So You Think You Can Dance" ... reading the alleged message out loud, and putting an end to speculation it was inappropriate.

Morrison, who was recently released from the show for failing to follow "competition production protocols" is clearly agitated in a video he posted on Instagram, captioned, "Just to clarify .."

He opens it by saying, "It's unfortunate that I have to sit here and defend myself and my family against blatantly untrue statements made anonymously, but I have nothing to hide. So, in the interest of transparency ... I will read to you the one message I wrote to a dancer on the show."

He then reads the message, which we've verified as being sent on April 25 at 12:34 AM and says, "Hey! It's Matthew. If you don't mind, would love to get your number and talk you through some things ..."

Morrison then explains he wanted to connect with the contestant because they share a "mutual respect" for a choreographer, and he wanted to get said choreographer a job on the show.

Our sources say it was the contestant who reported the message to show producers as being potentially problematic.

Sources close to Morrison tell us he was unaware of the no contact rule in his judge's contract. We're told he's worked on dance shows in the U.K. where collabing with contestants was encouraged ... and didn't think it was going to be an issue.