NASCAR

So ... Danica Patrick's exposed nipple is hanging out on a Sports Illustrated website.

The racy pic of the NASCAR driver is featured in a "Throwback Thursday" photo gallery on S.I.'s "Swim Daily" website ... which features a "selfie" style photo shoot of Danica from 2008.

We called S.I. to find out if it was a mistake ... or one of those intentional "nipples are artsy" sort of things ... but so far, we haven't heard back.

Jimmie Johnson tells TMZ Sports ... Donovan McNabb was talking out of his ass when the QB said race car drivers aren't athletes ... and JJ says he'll crush him on the track to prove it.

Of course, the racing world went crazy this weekend ... when DM went on Fox Sports 1 and told Erin Andrews, "Do I think [JJ's] an athlete? Absolutely not."

FYI -- ESPN ran a Sports Science special on racing back in 2011 and said that testing proved race car drivers have some of the best reaction times, endurance, strength and concentration in any sport.

Jay-Z is putting Jerry McGuire to shame -- because his budding sports agency just signed three-time NBA all-star Kevin Durant.

The OKC Thunder superstar just posted an Instagram of he and Jay signing docs that make him Roc Nation Sport's newest client.

Durant is the latest in a growing list of HUGE athletes jumping ship to Jay's new venture ... like NY Yankee Robinson Cano, NASCAR superstar Dale Earnhardt Jr., and NY Jet Geno Smith

Durant is Jigga's first NBA star.

The Wisconsin racetrack where Dick Trickle forged his legacy -- winning TONS of races en route to becoming a NASCAR star -- is honoring the driver with a special pre-race ceremony when stock car season kicks off later this month, TMZ has learned.

It's all happening at the Wisconsin International Raceway in Kaukauna, WI (just south of Green Bay) -- where Trickle won so many races during his pre-NASCAR career, track officials named a building in Turn 2 the "Dick Trickle Pavilion."

We've learned ... officials at the W.I.R. have greenlit plans to commemorate their local hero with a memorial lap in Dick's honor on May 30 ... with the pace car carrying a black flag.

A rep for the company says Trickle was "a true champion, good friend and will be missed by all."

As we previously reported, officials say Dick died Thursday from an apparent self-inflicted gunshot wound in North Carolina.

Dick Trickle suffered from excruciating pain under his left breast in the days before he killed himself ... and was "very down" about his health situation in his final days, this according to Trickle's brother.

Chuck Trickle opened up to both TMZ and the Las Vegas Review Journal ... saying Dick's death from an apparent self-inflicted gunshot wound is "a shock to me ... it's real hard to think about."

Chuck says he spoke with Dick just last week ... and the former NASCAR driver was complaining about a severe pain under his left breast that seemed to be getting worse.

"He was having a lot of issues w some pain ... he had sharp pain by his left breast and constant hard pain," Chuck told TMZ.

Chuck says Dick went to the doctor twice a day in an effort to remedy the issue -- and underwent numerous MRIs and CAT scans -- but doctors were never able to determine the cause of the pain.

“He was very down,” Trickle said ... adding, “He more or less said he didn’t know how much longer he could take the pain.”

As TMZ first reported, Trickle left a suicide note at the North Carolina cemetery where he died -- it's unclear if the note explains why Trickle decided to take his own life.

Dick Trickle sounded extremely calm for a man planning to kill himself when he called 911 yesterday and told the operator, "There's going to be dead body ... suicide."

TMZ has obtained the 911 call made by the NASCAR driver moments before he shot himself. In the call, Trickle gave the dispatcher very detailed instructions about where to find the body at Forest Lawn Cemetery in North Carolina.

When the dispatcher asked Trickle if he was calling about someone else, Trickle replied, "No, I'm the one."

The operator begged Trickle to wait for help ... but her pleas went unanswered.

When emergency personnel arrived at the scene, Trickle's body was discovered right where he said it would be.

Officials say Trickle died from an apparent self-inflicted gunshot wound to the head.

2:44 PM PT -- NASCAR Chairman and CEO Brian France just commented on Trickle's death ... saying, "Our thoughts and prayers go out to the family and friends of Dick Trickle on his passing today."

"Dick was a legend in the short-track racing community, particularly in his home state of Wisconsin, and he was a true fan favorite. Personalities like Dick Trickle helped shape our sport. He will be missed."

2:28 PM PT -- We're told ... Trickle's body was removed from the cemetery and has been transported to a nearby hospital.

2:17 PM PT -- Multiple sources who knew Trickle tell us he had been sick for a while and depressed. We're not sure what kind of illness Trickle had been suffering from.

1:51 PM PT -- Law enforcement sources tell TMZ ... Trickle did leave a suicide note at the death scene. The contents of the note are unclear at this time.

Former NASCAR driver Dick Trickle is dead ... apparently having taken his own life with a self-inflicted gunshot wound. He was 71 years old.

Cops in North Carolina say Trickle shot himself at Forest Lawn Cemetery in Lincoln County at 12:02 PM today.

Officials say they received a phone call before the shooting in which the caller said there would be a dead body at the cemetery and it would be his.

Operators scrambled, trying to place a return call, but there was no answer.

When emergency responders arrived, they found Trickle's body near his pickup truck.

Trickle was a fan favorite in NASCAR -- often smoking cigarettes while he raced.

Dick won the NASCAR "Rookie of the Year" award in the Winston Cup in 1989, when he was 48 years old.

Trickle was also beloved by the gang on "SportsCenter" -- Keith Olbermann and Dan Patrick used to almost always report his race results -- no matter how poorly he finished -- just because they were amused by his name.

Olbermann just tweeted ... "No sports figure Dan + I had fun with took it more graciously. In fact, gratefully."

He added, "Trickle helped mainstream NASCAR coverage on @SportsCenter We gave prominent attention to him, then his races, then ALL races."

Racing legend Darrell Waltrip thinks NASCAR should follow in hockey's footsteps ... and let drivers punch out their differences -- and each other -- after races. Beats left turns, right?

Kyle Busch -- one of NASCAR's famous hot-heads -- has signed on for some professional help from Charlie Sheen ... on his TV show, "Anger Management" ... TMZ has learned.

Sources connected to the show tell us Busch just signed the deal -- in the last 30 minutes -- to play himself in one episode of the FX comedy. He'll be seeking counseling ... we presume for road rage ... from Charlie's character.

Busch -- the most successful driver, in recent years, for Joe Gibbs Racing -- has more than earned his nickname ... "Wild Thing" with his antics on the track ... and off.

We're told Busch wanted to do the guest spot because he's a "giant Charlie Sheen fan" ... and loves the show.

Don't blame 50 Cent for the awkward encounter he had with Erin Andrews at the Daytona 500 last week -- the hottest woman in sideline reporting says the blame lies squarely with her.

During the big race last Sunday, Erin was searching for Danica Patrick (to no avail) when she ran into Fiddy and ... well, it was weird.

But yesterday at LAX, Erin told our photog she was so frazzled in the moment ... the entire encounter was totally her fault and she's actually good friends (and even business partners) with 50.

The old "it's not you, it's me" -- we've heard that one before.

It's the biggest question Daytona 500 champ Jimmie Johnson -- and every other NASCAR driver -- faces during a grueling 3-4 hour race ... HOW DO YOU GO TO THE BATHROOM??? And JJ actually gave us an answer.

Jimmie -- who was out in NYC yesterday -- told TMZ, "Some guys just go." Yes, in their pants.

But the 5-time Sprint Cup champ adamantly denied ever wetting himself, adding ... "I never have. Of course I wouldn't do that."

SURE YOU WOULDN'T.

Hagar tells MTV, “It was real. They were plugged into me. It was a download situation … or, they uploaded something from my brain, like an experiment ... They were tapped into my brain and the knowledge was transferred back and forth."

Hagar insists the whole thing went down in Fontana, CA -- home to a NASCAR track.

According to the ex-rock star, it wasn’t his first extra-terrestrial experience either -- claiming he saw his first UFO when he was just four years old, hovering over a field near his home.

Patrick's green #7 got caught in a pileup coming out of turn four at Daytona International Speedway, and she couldn't avoid the wreckage in front of her.

At least she got her first Daytona wreck out of the way.

Indy race car driver Danica Patrick has yet to learn that the funny little pedal on the left is the brake.

Cops confirm Patrick was busted earlier this month in Scottsdale, Ariz. for driving 54 in a 35 -- 19 over the speed limit -- which bested her last run-in with the fuzz where she was going 57 in a 40 -- only 17 over.

Danica Patrick isn't just dangerous behind the wheel of an Indy car, cops say she also posed a threat on the mean streets of Scottsdale, Ariz.

Court docs which show the race car diva was popped by Scottsdale P.D. back in January for doing 57 in a 40 mph zone. But here's the kicker -- Danica was ordered to take defensive driving school to get the ticket dismissed!

Guess the class worked -- because 40 days after Patrick finished her court-ordered traffic class, she won her first Indy race.