UFC

Boxing legend Ricky Hatton says he has a lot in common with Conor McGregor -- and he's even got some advice for the UFC superstar.

Hatton was a damn good boxer back in the day -- racking up a 43-0 record before finally losing to Floyd Mayweather in 2007.

We asked how he felt about comparisons between him and Conor over the years -- and Hatton seems pretty flattered by it ... explaining why he thinks they're two of a kind.

BTW, Ricky has now transitioned into trainer -- and is getting Sergey Rabchenko ready for his big Showtime fight Saturday night at Barclays Center.

Meantime, check out Hatton's greatest hits -- dude was beast.

Nate Diaz just gave the blow-by-blow on how Justin Bieber put an END to their famous celebrity beef back in March -- and the whole thing is pretty hilarious.

Of course, the two had gone back and forth on social media after the McGregor fight -- with Nate ultimately coming on the "TMZ Sports" show and saying, "F*** that fool."

As fate would have it, they came face-to-face in a Hollywood nightclub a few days later -- but Bieber's no dummy ... he immediately tried to bury the hatchet before things popped off.

You gotta hear Nate tell the story on "Conan" Tuesday night ... not only did they bro-hug it out, but they're boys now!

UFC badass Valentina Shevchenko -- who beat up Holly Holm this weekend -- tells TMZ Sports she wants the belt ... BADLY ... and she's ready to go through Amanda Nunes or Ronda Rousey to get it.

FYI, Shevchenko lost to Nunes by unanimous decision back in March -- but Valentina says she's at the top of her game now ... and is champing at the bit to get the current UFC women's bantamweight champion back in the Octagon.

"I know it will be a very difficult fight for her," Shevchenko said ... "I want it. I want it very much."

She also pitches her case to UFC honcho Dana White about why she should get the rematch.

Two titans of sport ... not one single chest hair.

Cristiano Ronaldo and Conor McGregor came face-to-face in Vegas this weekend ... and immediately took their shirts off.

He's already a UFC Hall of Famer ... but B.J. Penn could have been EVEN BETTER ... so says Dana White, who tells us the guy had the talent be one of the greatest MMA fighters of all time.

We spotted White in NYC -- and asked if there was a fighter who had insane raw talent ... but didn't have the drive to reach their full potential.

"B.J. Penn," White said ... "B.J. Penn probably should have been one of the best ever ... to ever live ... to ever do it. B.J. was so talented."

"I think B.J. in his own words would go back and do things differently if he could."

B.J. was 28-10-2 in his MMA career -- but couldn't figure out a way to beat guys like Frankie Edgar (lost 3 times) and Georges St-Pierre (lost twice).

UFC honcho Dana White took the stage Tuesday evening at the Republican National Convention and praised Donald Trump as a loyal friend who's had his back since day 1.

White opened his speech by saying "I'm sure most of you are wondering, 'What are you doing here?'" -- but went on to explain how Donald was the first person to support UFC when White and his partners bought the business in 2001.

Long story short, White says Trump is the kind of fighter America needs ... and has all the tools to be a kickass president.

White appeared on the "TMZ Sports" TV show a while back and explained why he's Team Trump for life.

Brock Lesnar may have caught a break -- because despite the fact he allegedly tested dirty TWICE, he'll only face punishment for one violation ... sources familiar with the situation tell TMZ Sports.

It all has to do with the dates Brock's samples were collected ... and when he was notified about the results.

In Brock's case -- he was tested on June 28th and July 9th. But he wasn't notified that his June test came back dirty until July 14th ... 5 days after his second test.

Our sources tell us ... because he wasn't notified until after the second sample was collected, he will only be punished for one violation.

The punishment for a first time banned substance user can range from a warning to a 2 year suspension ... though it can be raised to 4 years if the infraction is determined to be an "aggravating circumstance."

Brock Lesnar tested positive for a banned substance on the DAY OF UFC 200 ... this according to the UFC.

The U.S. Anti-Doping Agency notified the UFC that a sample collected on July 9th tested positive for the same substance that was found in Brock's 1st failed test, which went down on June 28th.

Holly Holm says she's pretty damn sure she's clean -- because she's been tested for PEDs 14 TIMES in 2016 ... one more than Conor McGregor.

Holm was addressing the media before the big fight this weekend with Valentina Shevchenko -- when she said she's been more than any other fight in the UFC.

"Friday was number 14 just within the last year."

In video posted by MMAFighting.com (around 36:25), Holm says officials usually collect both blood and urine samples for testing.

With Jon Jones and Brock Lesnar dominating the news for allegedly flunking PED tests -- fighters need to be more careful than ever about what they put into their system.

One more thing ... Holm was also asked if she regretted taking a fight with Miesha Tate before a big money rematch with Ronda Rousey.

"I 100 percent stand by [my decision]," Holm said ... "because we're still waiting for Ronda to come back."

How does Conor McGregor relax when he's in L.A.? Segway trips on Venice Beach.

Check out the UFC superstar rollin' through the area ... hittin' hat shops, sippin' on pressed juice and most importantly -- taking pictures with any fan who wants a shot!

Love him or hate him -- gotta admit, Conor's always good to his supporters.

Jon Jones says he's NOT A CHEATER -- and says he still believes he can clear his good name.

Of course, Jon was yanked from UFC 200 after he tested positive for 2 banned estrogen blockers -- which are typically used in tandem with certain performance-enhancing drugs to limit side effects.

He has been temporarily suspended from fighting in Nevada -- and a hearing is expected for later this year.

But Monday afternoon, Jon went to Twitter to plead his innocence.

"Don't write me off just yet, I know in my heart that I'm not a cheater," Jones said.

"I trust in the system to help me prove it."

CM Punk doesn't deserve to be in the UFC -- and will likely get his ass beat in his UFC debut because he's not a real fighter ... so says UFC fighter Lorenz Larkin.

Larkin has been a pro fighter since 2009 -- and essentially lays out why allowing the former WWE superstar in the Octagon is an INSULT to the sport.

You gotta watch this clip ... Larkin throws the SHADE OF THE YEAR -- and says he'd be worried for Punk's life if the UFC ever allowed the two to square off.

"The UFC doesn't have enough insurance for what I'd do to him."

FYI, Punk makes his debut at UFC 203 in September -- we'll see if Larkin's right.

Jean-Claude Van Damme has a brand new 'Kickboxer' costar -- UFC fighter Roy "Big Country" Nelson ... and we're told the heavyweight CRUSHED IT on the set.

Conor McGregor's on the fast track to ANOTHER ass whoopin' ... so says Urijah Faber who tells TMZ Sports the Irish superstar just doesn't have what it takes to beat Nate Diaz.

Faber tried to help Conor prepare for his last fight against Diaz, but his advice fell upon deaf ears.

Now, Urijah says ... despite all of the positive things Conor has going for him -- like toughness and skill -- a victory in the rematch is simply out of the question.

By the way, we also asked 37-year-old Urijah if he was planning on retiring any time soon ... check out what he says.

Mark Hunt is FURIOUS over Brock Lesnar's potential failed drug test ... DEMANDING half of B.L.'s UFC 200 winnings ... or he's bolting the UFC.

Hunt laid it all out on his website Friday night ... saying, "I've told Dana I want half of Brock's purse."

FYI -- Lesnar reportedly made $2.5 MILLION ... plus a percentage of the massive pay-per-view take.

"This is the third time I've had to fight a cheater in my career. The other two times I didn't ask for compensation, but this is the third time and I'm sick of them getting away with cheating."

If he doesn't get Brock's cash, Hunt says he wants out of his UFC deal. "I've told Dana that I want a release from the UFC if they don't sort this out."

The UFC has not yet responded to Hunt's ultimatum.

Nooooooooooooo!!!!!

The UFC announced Brock Lesnar has been flagged by the U.S. Anti-Doping Agency for a potential violation stemming from a pre-UFC 200 test.