Hook Ups

Katharine McPhee's estranged husband gave her a hand Tuesday ... a very gentle hand.

It's a stark contrast to her split with Nick Cokas, which allegedly came after Katharine was photographed sucking face with her "Smash" director Michael Morris. Katharine claimed in the documents she was already separated from Nick, but he says they were still together.

But things change ... or do they? A source close to Katharine insists Katharine and Nick had a friendly business breakfast in West Hollywood. He's still involved in her music stuff.

Tyga refuses to let anyone tell him where he can bring his underage GF, Kylie Jenner ... so he ignored a college's request to keep her off campus during his concert ... TMZ has learned.

Tyga performed at Cal State Fullerton's Spring Concert this past Saturday, and according to our sources ... concert organizers told him he should NOT bring 17-year-old Kylie to the show.

We're told not only did the university find their relationship questionable, but the show was 18 and older. Tyga must have known he had the school by the balls -- they couldn't afford to bring in another act at the last minute -- because he went ahead and brought her anyway.

While he was performing ... she was chilling at a table full of chicken wings and other appetizers -- which we're told Tyga suddenly demanded when he arrived ... an hour late.

Organizers didn't want to risk him bailing completely ...so, we're told they just let it go.

Kylie's presence didn't go unnoticed by the students, with one tweeting, "CSUF said guests must be 18 or over to enter spring concert but Tyga brought Kylie as his guest."

As we reported ... Tyga ran into the same situation during a gig in November, but opted to boycott the club. The couple put their age issues aside Monday as they flew out of LAX -- airlines don't care if he travels with a minor.

Travis Barker has decided to enter the UFC ... sorta ... 'cause he's dating the league's most famous ring girl, Arianny Celeste.

Sources close to the couple tell us ... the two have been dating for several months. We're told they met at one of Travis' concerts and the sparks flew from there.

Ever since, we're told they've been "inseparable" ... and Travis is telling friends he thinks she could be "the one."

In fact, Travis recently introduced Arianny to his kids -- which is a pretty HUGE step.

Mazel!

Selena Gomez must be exhausted ... 'cause the chick was running all through Justin Bieber's mind during Monday night's Met Gala -- at least that's how JB made it seem on the way out.

Justin and Selena have been broken up for months, but as he left the ball -- which Selena also attended -- Biebs went out of his way to throw out a line that was loaded down with bait for his ex-gf.

Watch ... he absolutely, almost desperately, wanted to make a point about SG's dress last night.

Word on the street is she just broke up with Zedd, so uhh ... never say never?

Then again ... Justin didn't seem to be losing sleep over her while partying with Leo DiCaprio at Rihanna's after-party. #TurnUp

Call it kismet, or karma, or whatever ... there's a chance Rachel Uchitel and Tiger Woods will go another round.

Rachel tells us she just broke up with baseball star Bret Boone, days after Tiger called it quits with Lindsey Vonn.

So the question ... does Mistress #1 still have a hankerin' for the golfer with a roving eye?

Sources close to Rachel say she told them, "We both loved each other very much," but adding, "It was humiliating and devastating to have to break up that way."

Now the opening ... Rachel says, "He would have to do some major apologizing to get back in my good graces, that's for sure."

No word from Tiger, but remember, when he was banging Rachel he was at the top of his game.

American Pharoah is gonna be more like American Gigolo after this weekend -- 'cause now that he's a Kentucky Derby champ, he's gonna get sooooo much horse ass ... so says his trainer Bob Baffert.

The legendary horse trainer touched down at LAX after watching A.P. dominate at Churchill Downs -- Baffert's 4th time winning the Derby -- and told us Pharoah's stud value just went through the roof.

"He's gonna get a lot of action," Baffert said.

Of course, Pharoah still has to get through the Preakness and the Belmont Stakes before he becomes a professional impregnator -- but if he wins those too ... it'll raise his price EVEN MORE!

Hilary Duff is the next 'Bachelorette' ... of Tinder -- she's shooting footage of all her dates setup through the app ... and there's a chance it could turn into a reality show.

Hilary recently copped to right swiping a bunch of guys on Tinder -- 9 at last count -- and even went on a first date this week with one of them. Sources with direct knowledge tell TMZ ... cameras were rolling during the date at a bowling alley.

We're told Hilary plans to shoot more footage as she dives into the dating world ... and hopes to use it to develop a reality show -- that would focus on her life as a new divorcée. Think 'Stella' getting her groove back ... but whiter.

Hilary's rep had no comment about a potential reality show.

He may be the heavyweight champion of the world, but Deontay Wilder still has goals -- telling TMZ Sports he wants to bang Nia Long ... in a sex scene for a Hollywood movie.

See, Wilder has dreams of becoming an actor in addition to the whole boxing thing ... and clearly, he likes the idea of doing some romantic work with the star of "Love Jones," "The Best Man" and "Big Momma's House."

In fact, Wilder says he's had a HUUUGE crush on Long for years ... and in the clip, makes the ultimate pitch to be her leading man in the sack.

You gotta watch the clip -- dude's HILARIOUS!

So on the same day Michelle Rounds filed for sole custody of the child she shares with ex Rosie O'Donnell, she hit the town with a smoking hot model. What are the odds????

Rounds was out Tuesday night at Madera Kitchen where she walked out with her arm around Carmen Ortega ... who once dated Reggie Bush and was also possibly maybe the reason Jason Derulo and Jordin Sparks split.

We can't say Rounds and Ortega are together. In fact, a rep for Ortega says they're just working on a clothing line together -- but Rounds still went out of her way to snuggle close to Ortega for the cameras to see.

Not that we can blame her.

Hilary Duff's having NO trouble easing into single life ... not with her Tinder profile blowing up like its. Hilary says she's currently right-swiped NINE guys -- and is even ready to meet one of 'em in person.

The lucky guy is way different from anyone else she's ever dated -- 'cause he's what Hilary calls ... a "normie." Oh, the horror.

Russell Wilson is having one hell of an off-season ... he just walked in to the White House State dinner with Ciara on his arm .... and she's looking DAMN FINE!!!!!

Rumors had been swirling about the Seattle Seahawks QB secretly dating the R&B singer ... but now, it appears to be official -- with Wilson bringing her as his date for dinner with President Obama and the Prime Minister of Japan.

Before Ciara came into the picture, Wilson -- who divorced his wife last year -- was spotted out with Sports Illustrated Swimsuit Edition model Samantha Hoopes ... but clearly, she's out -- Ciara's in.

Mazel!

Hilary Duff is a right-swiping fool ... and is not only confirming that rumored Tinder profile really IS her -- but says she's going on her first Tinder date tonight ... with a regular ole non-celeb dude!

Hilary dropped her dating bombshell Tuesday morning with "Valentine in the Morning" on 104.3 FM in L.A. -- and opened up about what she's looking for on Tinder. Hint: shirtless muscle heads need not apply.

Sounds like Duff is kinda hooked on the app ... saying it's the first time in her life she's getting a chance to hook up with a "total normie." It also sounds like she's totally over her estranged hubby, Mike Comrie.

Pretty amazing to hear a celeb cop to her (formerly) secret life on Tinder. We sense a surge in subscriptions coming.

Rob Gronkowski's new girlfriend just scored her first big modeling campaign -- landing a gig as the "brand ambassador" for a big watch company ... and she looks good.

As we previously reported, Gronk is all BF/GF with Camille Kostek ... a former New England Patriots cheerleader, news anchor and model.

Now, Kostek is the "fresh face" for the Benrus Watch Company -- which says it hired Kostek because "she represents all of our standards; beauty, intelligence, and a commitment to excellence."

Weird, that last one is more of a Raiders thing ...

Anyway, congrats!

Amber Rose and rapper Machine Gun Kelly are on like Donkey Kong ... because nothing screams "together" like an airport pickup.

Rose met Kelly at baggage claim as he helped himself to handfuls of booty ... so say other disembarking passengers.

Kelly may want to talk things out with his boy Wiz Khalifa -- the guy Amber called the love of her life earlier this month. They share the beat in "Mind of a Stoner," but that doesn't necessarily mean he's cool with sharing the mother of his kid.

We can't figure out whether she has a type.

Madonna tried to holla at a hot shirtless male model -- who's 33 years younger than her -- but proving she' still got game ... we found out the guy's willing to give her a shot!

The model's name is Andrea Denver -- and his bod is definitely worthy of Madge's Instagram, which included the caption: "8 pac!! Hell to the yeah!!!" She threw in a bunch of heart emojis too ... which might come off as kinda thirsty, except for the fact Andrea's totally down.

Sources close to Andrea tell us he saw the IG and his reaction was, "I'd definitely go on a date with her." Taking a page out of Drake's playbook ... we're told Andrea also gushed the 56-year-old is "really attractive" -- and he's always been a big fan.

Madonna and Andrea have never met, but according to our sources ... he's excited there's now a chance. He's hoping she follows through and hooks it up.

Even if the romantic thing doesn't flesh out -- Andrea says he'd be down to work in one of her music videos. He's got experience with Taylor Swift and J.Lo ... music vids, that is.

As for the fact she could be his mother -- we're told Andrea says age doesn't scare him, since he's more interested in a woman's personality.

#MILFpower

Blac Chyna says Tyga didn't just text her out of the blue this week trying to get back with her ... she says he's been making that play for 7 months.

Sources connected with Blac Chyna tell TMZ ... the text -- in which he said "I want to be with u" -- was the last in a flurry of texts, conversations and private face-to-face meetings in which he made his play to reconcile their relationship.

Sources close to Chyna says she never believed he was physically with Kylie Jenner -- partly because she's 17, and partly because they were all neighbors and close to the Kardashian family. She says she believed Tyga when he called out the media for suggesting he was dating Kylie, but doesn't believe it anymore.

Blac Chyna posted Tyga's texts out of anger, but she claims she wants nothing to do with him anymore. It's complicated by the fact that they have a kid together.

As for Tyga, he has never said he's with Kylie and in the past has denied it ... but he's recently insinuated it, and even put it in writing.