Just when you thought the dysfunction couldn't get any worse in Houston ...

J.J. Watt -- arguably the Texans' greatest player EVER -- has just been released by the team ... this after the 3-time NFL Defensive Player of the Year says he asked to be let go.

Watt made the shocking announcement Friday morning ... recording a video explaining the move.

"I have sat down with the McNair family and I have asked them for my release and we have mutually agreed to part ways at this time," Watt said.

Watt, who thanked Houston fans, teammates, coaches and ownership ... added, "I'm excited and looking forward to a new opportunity."

Watt was picked in the 1st round of the 2011 NFL Draft by the Texans, and he's absolutely shredded the league since.

Despite battling a myriad of injuries, Watt made 5 Pro Bowls and 5 All-Pro teams ... and recorded a staggering 101 sacks in 10 seasons.

Watt, though, has clearly grown tired of all the issues with the Texans.

The team has traded star player after star player ... and it now is in a massive beef with its MVP-caliber quarterback Deshaun Watson, who also has reportedly asked to be traded from the team this offseason.

It's unclear where Watt will land as a free agent now ... though joining up with his little brothers, T.J. Watt and Derek Watt, in Pittsburgh seems like a very possible outcome.

In fact, ESPN is reporting J.J. Watt has talked to his 2 brothers about joining them in Pittsburgh. The Steelers probably can't afford him, but it's been discussed among the Watt bros.

Texans Chair and CEO Cal McNair also issued a statement ... saying, "J.J.'s impact on not only our organization, but the entire Houston community, is unlike any player in our franchise's history."

"I told J.J. earlier this week that we will forever consider him a Texan."

Story developing ...