160 pounds of dynamite exploded right in Seth Rollins' bean bag Monday night ... when Jon Stewart delivered an effective low blow right in the middle of "Monday Night Raw."

Stewart had just finished berating Rollins in front of a live crowd in Newark, NJ -- the latest round of trash talk in their public spat.

But when Rollins decided enough was enough and started roughing up "The Daily Show" host in the ring -- Stewart took advantage of a distraction ... and kicked Seth's balls up into his throat.

Someone get that man some ice.

WWE stars Rusev and Lana like to live dangerously -- the NOT married or engaged couple just signed on the dotted line to buy a house together after dating for less than 2 years.

Wrestling fans know Lana is Rusev's manager in the ring -- but now they're finally confirming rumors they're dating ... and it must be serious since they purchased a 4 bedroom, 4 bathroom home in Nashville.

It's a pretty sweet deal -- 11.56 acres with a pond, hot tub, basketball court and more in Music City ... all for $644K. We're told they chose Nashville because it's easier for them to travel from the middle of the country.

John Cena doesn't think there's an age limit on weight room domination ... telling TMZ Sports 69-year-old Vince McMahon is an absolute TERROR on the racks.

The WWE superstar was out in NYC (wearing only a t-shirt in the freezing weather) when we asked him about VM's recent Men's Fitness Magazine cover where the guy looked like an AARP Incredible Hulk.

Check out the clip -- Cena says that McMahon's biceps aren't just for show and the guy can lift like a man half his age ... and even rivals Cena himself.

Makes you want to call your granddad ... and ask him why he's slacking off.

Jon Stewart wanted a piece ... HE GOT THE PIECE!!!!

WWE superstar Seth Rollins hijacked Stewart's "Moment of Zen" on "The Daily Show" Thursday night ... in response to the smack talk video that Stewart recently made.

But Rollins didn't just talk the talk ... he then snuck up behind Jon and put him in a HEADLOCK!!!

It was pretty hilarious ... and fulfilled the promise Rollins made on "TMZ Hollywood Sports" ... when he said he'd whoop Jon's ass for running his mouth earlier this month.

And apparently the drama will continue ... with Jon promising to face off with Rollins on next week's "Monday Night Raw!!!!"

Wrestling legend Rey Mysterio is done working for the WWE ... TMZ has learned his contract expired Thursday, and both sides have decided to part ways.

A rep for WWE tells us, "Rey Mysterio is no longer under contract with WWE."

Rey appeared in a video for a rival wrestling company in Mexico last summer ... and launched his #FreeRey campaign to get released from his WWE contract.

Well, Rey's free now ... but not because of his campaign. To be clear ... we're told his contract just expired ... he was NOT let out of his deal.

Sources close to Rey tell us he's excited to start working again because he's 100% healthy. Producers at MLW radio -- a wrestling podcast -- say they'll be doing a live interview with Rey ... taking place the weekend of WrestleMania 31.

We've gathered 25 of the sexiest social media shots that make this Bella twin a clean finish for your Woman Crush Wednesday. Don't tap out until you've seen them all!

This is not going to make twerking cool again -- in fact, former WWE star Chyna put the final nail in the dance craze's coffin.

Chyna dropped the video on her social media channels claiming one of her fans requested the twerk session ... and she was happy to oblige.

The only problem? Well, take a look ... think, mom from Orange County who just watched a Miley Cyrus music video.

The WWE says it has proof that CM Punk NEVER had a baseball-sized lump on his back at the Royal Rumble -- and insist they have the video that shows he's lying through his singlet.

Punk first brought up the alleged lump on a podcast back in November -- when he claimed he was misdiagnosed by a WWE ringside doctor ... and it eventually led to a life-threatening staph infection.

The doctor filed a $1 million defamation lawsuit against Punk -- and now, the WWE is making it clear they have the doc's back.

"WWE continues to have the utmost confidence in the ability and expertise of our world-class team of physicians, including Dr. Amann," the organization said in a statement.

This is where it gets aggressive ...

WWE says it completed a full investigation into Punk's allegations and made the following conclusions:

-- "CM Punk did not discuss this alleged condition with WWE’s team of physicians and trainers, nor did he discuss it with anyone in our Talent Relations department. WWE has no medical records documenting this alleged condition.
-- The first time WWE was made aware of this alleged condition was when we received a letter from CM Punk’s attorney on August 22, 2014 after WWE terminated his contract.
-- "There is clear video evidence from the 2014 Royal Rumble, which allows all to decide whether there is any appearance of a baseball-sized growth on CM Punk’s back."

Check out the clip ... you seein' a lump?

Two former WWE superstars have been hit with a huge lawsuit from the WWE ringside doctor -- who claims the duo defamed him on a podcast ... when they trashed him over the way he treated a growth on CM Punk's back.

The man behind the lawsuit is Dr. Chris Amann -- who claims Punk and Colt Cabana defamed him on Colt's "Art of Wrestling" podcast back in November ... when Punk spoke out for the first time about his departure from WWE.

During the podcast, Punk repeatedly tore into Amann -- essentially saying he was a crappy doctor.

Amann says the two also claimed he misdiagnosed a growth on Punk's back -- a growth that Punk says later turned into a full blown staph infection.

But Amann says it's all BS -- claiming the statements are false and defamatory ... and now he wants the wrestlers to pony up more than $1 million in damages to his reputation ... plus punitive damages.

Colt and Punk had no comment about the lawsuit.

WWE superstar Seth Rollins has a NEW message for Jon Stewart -- BRING IT ON!!!

After the "Daily Show" host called him out in a smack talk video, Rollins responded on "TMZ Hollywood Sports" on Reelz and fired back at Stewart ... calling him old, frail and a total wuss.

We raised the issue that Stewart was a college athlete who played soccer for William & Mary ... but Rollins didn't seem fazed. In fact, he talked even more smack.

"People think WE take falls? Look at soccer players!"

There's more ... much, much more. Can't wait to see if Stewart hits back -- again.

Make sure to check out "TMZ Hollywood Sports" on Reelz -- weekdays 3 PM ET, 6 PM PT.

WWE superstar Seth Rollins has a HUGE problem ... there's "160 pounds of dynamite" ready to explode on his ass for talking smack about "The Daily Show" ... and that man is Jon Stewart.

Stewart just shot a video response to Rollins -- who went on "Raw" this week and said he should take over for Jon ... who was UNWATCHABLE as the host of the Comedy Central show.

Well, Stewart didn't take too kindly to the smack talk ... and came back HARD at Rollins with some threats of his own ... and it's EPIC!!!

Fighting words from The Miz ... this time, the WWE superstar tells TMZ Sports he honestly believes he's the GREATEST actor in wrestling history -- and specifically calls out The Rock.

In Miz's defense, it sounds like he'd been drinking on his way out of Warwick in Hollywood Wednesday night -- but he couldn't be more clear, "There is no WWE superstar who's ever been a better actor than me."

For the records, Miz's biggest credits:

-- "The Marine 3: Homefront"
-- "The Marine 4: Moving Target"
... and he played himself in "Scooby-Doo! WrestleMania Mystery"

The Rock's biggest credits:

-- "Fast Five"
-- "Fast & Furious 6"
-- "G.I. Joe: Retaliation"
-- "The Scorpion King"
-- "Walking Tall"
... and he's considered one of the biggest action stars in Hollywood.

Miz acknowledges The Rock is the #1 guy right now ... but insists, when it comes to talent, he's the one layin' the smackdown.

This is a GREAT moment caught on video ...

There we were, talking with WWE legend Shawn Michaels, when a MASSIVE dude nervously began to shuffle into the frame.

With a giant grin on his face, the man tapped Shawn on the shoulder ... and then, like a kid meeting his hero, he explained that he's a NY Giants player ... and Shawn was one of his idols growing up.

It's awesome -- the player is defensive tackle Jay Bromley, a 3rd round pick from Syracuse who just completed his rookie season.

Michaels is clearly impressed ... and the two proceeded to bro out ... even after Shawn broke the news he's a Cowboys fan.

The WWE has not said if there will be any live matches -- but it's not out of the question.

Earlier today, the Governor of Connecticut said the roads will be closed after 9 PM ... which would be in the middle of RAW's telecast ... and leave everyone in the XL Center stranded.

The WWE says it's not leaving Hartford out in the cold -- and will push the scheduled event to Thursday.

Arnold Schwarzenegger is going into the Hall of Fame ... not for acting or bodybuilding ... the former governor is being inducted for his contributions to wrestling.

TMZ has learned Arnold will be the next inductee WWE announces for their HoF's celeb wing -- featuring the likes of Mike Tyson, Pete Rose and Donald Trump.

Schwarzenegger is a long time wrestling fan whose appeared at many Monday Night RAW and Smackdown events. He also inducted legendary wrestler Bruno Sammartino into the Hall in 2013.

As we previously reported ... "Macho Man" Randy Savage will also be inducted into the WWE Hall of Fame during WrestleMania 31 weekend.

Wrestling legend Kevin Nash is officially off the hook in the Christmas Eve brawl with his son -- after cops determined "Big Sexy" wasn't the one who started the fight.

We broke the story ... both 55-year-old Kevin and his 18-year-old son Tristen were arrested at the family home in Florida after an allegedly drunken Tristen got physical with Kev.

According to the police report, Kevin took Tristen down to the ground hard after Tristen spit in his face. Tristen claimed Kev used his signature choke-slam move and caused him to black out.

But now officials tells TMZ Sports the State Attorney's office investigated the incident and determined "Mr. Kevin Nash was not the primary aggressor in this situation and that criminal charges should not be filed against him."

As for Tristen ... officials say he's not in the clear -- they're still investigating his role in the fight.