Katie Morgan Goes From Porn To Poker, Playing In WSOP

Katie Morgan is making one hell of a career pivot ... the XXX star is now playing poker on the biggest stage in the world!

The longtime adult film star and actress has officially gone from the set to the felt -- telling TMZ Sports she’s now competing in this year’s World Series of Poker Main Event.

"I've been playing poker basically my whole life. My grandpa taught me when I was five. And then I used to run a home game in L.A. for like 10 years, and I loved it," Katie said.

But, it was always casual ... that is, until she "ended up in a relationship with a professional poker player," and that's when she says she "really got into tournaments and stuff and playing live."

Morgan didn't waste any time going straight to the big leagues, either.

"I'm pretty good at it. So this year, I got backers who bought me in," Katie said. "They bought my action. That's what it's called in poker. And they're putting me in the [World Series of Poker] Main Event, and I'm so excited!"

If you know anything about the game, the WSOP is a huge deal.

"They're expecting like 12,000 players this year. So obviously there's going to be a wide range. There's people that just want to play and are not pros. And then there's the pro-est 'pros pros' from around the world. Literally everybody who's anybody in poker is here."

Of course, winning a tourney of this magnitude comes with a massive cash prize ... $10 million this year!

"That's life-changing money for anybody who gets that far up into, like, the final tables. That's nuts."