NASCAR

Patricia Driscoll testified in a Dover, Delaware court Tuesday about Kurt's alleged attack on her after one of his races in September. As we've reported ... Driscoll claims he choked her inside his motorcoach.

But sources close to Busch tell TMZ Sports his legal team has submitted a YouTube video of Driscoll as evidence. The video entitled "Pocket Commando" -- was posted earlier this year, and shows her at a gun range, showing off marksman skills and talking about the company she owns ... Frontline Defense Systems.

Driscoll calls herself a "commando mommy" on the video ... which we're told was shot and edited to pitch her as a reality TV star.

We're told Busch's attorneys will argue that Driscoll is a "trained assassin" who would have no reason to fear Busch. In fact, during Tuesday's hearing Busch's attorneys called her a "mercenary" out to ruin his career. Busch adamantly denies the attack.

Kurt Busch is adamant he did not lay a single finger on his ex-girlfriend during an argument back in September ... claiming she's making the whole thing up in a shameless cash grab ... sources close to Busch tell TMZ Sports.

As we previously reported, the NASCAR driver is being investigated for an alleged domestic assault on his ex Patricia Driscoll at Dover International Speedway on the weekend of Sept. 26th.

Sources close to Busch tell us ... the couple had broken up about a week before the incident -- and Busch was surprised when she showed up to his motorhome.

We're told ... Busch acknowledges they got into an argument -- but claims it never got physical.

Sources tell us ... Driscoll has told authorities Busch choked her inside the motorhome.

TMZ Sports spoke with Busch's attorney Rusty Hardin who tells us, "This allegation is a complete fabrication by a woman who has refused to accept the end of a relationship and Mr. Busch vehemently denies her allegations in every respect."

He adds, "The Dover Police Department has been informed that Mr. Busch will fully cooperate with their investigation and he expects to be vindicated when the entire truth of the situation comes to light."

And there's this -- we're told ... days after the incident, Busch's lawyer was contacted by a person claiming to represent Driscoll looking to negotiate a monetary settlement.

We're told that attorney resigned from representing Driscoll just days later.

We also spoke with police who tell us Driscoll didn't report the alleged assault until Nov. 5th -- six weeks after the incident.

The trackside brawl between Jeff Gordon and Brad Keselowski was 100% AUTHENTIC ... and not a scripted stunt to get ratings ... so says fellow driver Michael Waltrip.

Waltrip was at LAX on his way out of Hollywood after being eliminated from "Dancing with the Stars" -- when we asked about the bloody altercation at Texas Motor Speedway.

Of course, there's talk NASCAR put the drivers up to the fight to get a boost in ratings ... which are reportedly down 6% from last year.

But Michael ain't buyin' it -- telling us the rage couldn't be more real. Check out the clip.

Tony Stewart says he has not spoken with Kevin Ward Jr.'s family -- and doesn't feel he needs to -- explaining that he already has closure because he knows the deadly crash was an accident.

43-year-old Stewart just took questions from reporters ... and said he's offered to speak with Kevin's family but explained, "I don't need to talk to them for closure."

"I know what happened and I know that it was an accident."

Tony says, "I'm willing to talk to [Kevin's family] if it helps them ... I'm available if and when they want to talk."

Tony says he regrets choosing to race on August 9th -- and says he wishes he never got in the car.

"The first 3 or 4 days [after the accident], I didn't want to see anybody," Stewart said ... explaining that he basically went into seclusion following the incident.

He also says he doesn't know when he will race again -- but says today's news conference is a huge step toward re-entering the racing world.

Tony Stewart is off the hook criminally in the death of Kevin Ward Jr. -- but Ward's family is threatening to drag the NASCAR superstar into court with a civil lawsuit.

Ward's family members say they are infuriated because they believe Stewart "intentionally tried to intimidate Kevin by accelerating and sliding his car towards him, causing the tragedy."

As TMZ Sports first reported, the Ontario County Grand Jury in New York decided not to charge Stewart after reviewing evidence from accident reconstruction experts.

NASCAR star Tony Stewart will NOT face criminal charges in the death of Kevin Ward Jr. ... and in a shocking revelation, we now know Ward was high on weed at the time of his death.

TMZ Sports broke the story...the Ontario County Grand Jury in New York decided not to charge Stewart, after reviewing evidence from several accident reconstruction experts.

On the night of his death, Ward Jr. had gotten out of his car and was aggressively marching toward Stewart's car -- when he was struck. Now we know drug tests on the body produced proof Ward was under the influence of marijuana.

There was talk that Stewart was angry with Ward Jr. and may have intentionally veered his car into him -- but apparently the grand jury feels it was nothing more than a freak accident.

We're told the enhanced video showed Stewart did not make any sudden or suspicious moves on the track before his car collided with Ward.

IndyCar drivers = lean, mean driving machines.

NASCAR drivers = fatties.

... this according to IndyCar stud Helio Castroneves.

You gotta watch this clip -- Helio is hilarious ... and picks a "Talladega Nights" style feud with NASCAR ...starting with their "beer bellies."

Jean Girard would be proud.

Tony Stewart will get behind the wheel of his NASCAR ride again -- 3 weeks after his tragic on-track incident that killed fellow driver Kevin Ward Jr.

Tony's team, Stewart-Haas Racing, just announced he will be driving his #14 car this weekend at Atlanta Motor Speedway. Stewart sat out the last 3 NASCAR Sprint Cup races.

Cops have said it could be several more weeks before they determine whether Stewart will face any criminal charges for Ward's death.

Stewart sat out races that were critical, since he's battling to make the Chase -- NASCAR's playoff season. Presumably, he's taken the time to mentally recover from the incident -- which he called a tragedy.

NASCAR is laying down new laws after Tony Stewart's deadly accident, and the new bottom line is simple -- after a wreck drivers should stay in their cars and stay away from other moving cars.

NASCAR VP of competition Robin Pemberton announced the rule change this morning and acknowledged it is the direct result of Stewart driving over Kevin Ward Jr. during an dirt track race last Saturday night.

The new rule is drivers who get into a wreck should not get out of the car or remove any safety equipment until safety personnel tell them to -- and once a driver is out of the car he or she should not walk around on the track or approach moving vehicles.

The only exception would be if there's fire or smoke in the car ... then, obviously, drivers should get the hell out.

Ontario County Sheriff Philip C. Povero said he has now reviewed a second video from the fatal crash this weekend involving Tony Stewart ... but still does not see anything that indicates this was a criminal act.

Stewart has yet to be charged in the accident that claimed the life Saturday night of 20-year-old Kevin Ward Jr. Povero said the autopsy on Ward was completed and the cause of death was massive blunt trauma.

Don't blame Tony Stewart for the accident that killed Kevin Ward Jr. -- blame Ward ... at least that's the way the star of "Purge: Anarchy" sees it.

Frank Grillo broke down the horrific video of the Canandaigua Speedway tragedy with us Sunday night outside Madeo -- and he immediately stated, "Totally not Tony Stewart's fault!"

There's been a ton of speculation Stewart lost his temper, and cops are still investigating ... but Grillo explains why he thinks Tony did the best he could, under the circumstances.

Interesting theory.

10:50 AM PT -- Tony Stewart just released a statement, saying … "There aren't words to describe the sadness I feel about the accident that took the life of Kevin Ward Jr. It's a very emotional time for all involved, and it is the reason I've decided not to participate in today's race at Watkins Glen."

He added, "My thoughts and prayers are with his family, friends and everyone affected by this tragedy."

Tony Stewart is just trying to "get through today" … according to the exec from his racing team who announced Stewart was bowing out of today's NASCAR Sprint Cup Race.

Greg Zipadelli, a V.P. at Stewart-Haas Racing, was visibly emotional as he held the news conference in Watkins Glens, NY … describing Stewart's state of mind hours after he hit and killed fellow driver Kevin Ward Jr. during a race at a nearby track.

Zipadelli talked about Stewart's decision not to race today -- the team initially said he would -- calling it, "the right thing to do."

Reporters were instructed not to ask about the investigation into Ward's death.

7:45 AM PT -- Stewart has pulled out of today's Sprint Cup race. His team says Regan Smith will fill-in behind the wheel of Stewart's #14 car.

NASCAR superstar Tony Stewart drove his race car into another driver Saturday night … sending the man to the hospital where he was later pronounced dead.

Kevin Ward Jr. had gotten out of his #13 car after an on-track accident involving Stewart during a sprint car race (dirt track) in Canandaigua, NY.

Lakers star Nick Young just stepped on the same landmine that blew up in Donovan McNabb's face -- questioning whether NASCAR deserves to be called a sport.

Swaggy P was answering a simple enough question -- we asked him which sport is most affected by rain. Nick could have just said softball ... he was in the middle of a rain delay at a celeb game, anyway.

Instead he went and said this.

Someone get 5-time Sprint Cup Champion Jimmie Johnson on the horn ... we've got a new passenger for him.

Former NASCAR driver Leilani Munter WILL be taking her "Blackfish" car to Talladega, TMZ has learned -- all thanks to an incredibly generous donation from "Simpsons" co-creator Sam Simon.

As we reported, Leilani had desperately been trying to raise money to pay for the $115,000 fee to enter the car for a big race at an ARCA event at Talladega Superspeedway on May 3rd. As of our last story, she had raised only $7,500.

But that all changed last week -- Leilani appeared on Simon's radio show to talk about her car and orca-related activism ... and Simon was so moved, Leilani tells us, he donated the balance of her entrance fee immediately after the show ... $107,500.

We're told Simon visited Taiji in February (the place where "The Cove" was shot) and has become an outspoken advocate for the humane treatment of orcas. Leilani tells us, she plans to win the race on behalf of orcas around the world suffering in captivity.

Sam -- who has terminal colon cancer -- has vowed to give away his fortune before he dies ... specifically toward animal rights and feeding the hungry.

As if giving the world "The Simpsons" wasn't enough.

NASCAR legend Michael Waltrip had the thrill of a lifetime today -- HE MET DONNA SUMMER ... at least, he thinks he did ... despite the fact she died two years ago.

Waltrip was doing some pre-race work for FOX at the NASCAR Auto Club 400 race today when he THOUGHT he spotted the disco queen.

He even sang some, "Last Dance" on his way over to interview the icon ... who was really just a woman who kinda sorta looked like her.

Once he got there, it got more awkward when he attempted to talk to her -- "Hi Donna how are you? Enjoy the races today, I love your music. You’ve got a great body of work that you’ve put together!”

Moments later, he told team owner Richard Childress, “If you like Donna Summer, she’s right back there.”

Of course, Summer passed away in 2012 ... the woman at the track is just a NASCAR fan named Star Walker.

But Star says she was flattered by the mistake because she's a HUGE Summer fan -- and even went to Donna's induction to the Rock 'N Roll Hall of Fame!

Ya gotta watch the clip.