(CNN) He's one of horse racing's most celebrated trainers, but Bob Baffert had to defy his mother to reach the summit of the sport.

From humble beginnings growing up on a cattle ranch in Nogales, Arizona on the border with Mexico, the 66-year-old has saddled five Kentucky Derby winners and two Triple Crown champions in American Pharaoh and Justify in his illustrious career.

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It's earned him a place in the Hall of Fame, and made Baffert third on the all-time list of best trainers with more than $288 million in earnings, according to Equibase.

"I wanted to be a horse trainer against my mother's will," he told Aly Vance for CNN's Winning Post ahead of this year's Derby at Churchill Downs. "She said, 'how can you make living being a horse trainer in Arizona?'

"I just love being around horses. Once it gets in your blood, the passion, you can't get out."

As a youngster, Baffert would help his father show their cattle at shows in the region before they dabbled at training quarter horses -- the American breed famous for their sprinting prowess -- to race at various local tracks.

When he was old enough, Baffert learned how to ride and earned cash racing on dusty circuits around Nogales. Eventually, though, he realized his dream of becoming a full-time jockey wasn't going to materialize.

"I was too big, I ate myself out of a job," said Baffert, who has also trained seven Preakness Stakes winners and three Belmont Stakes champions.

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'Little fish, big pond'

Having promised his mother he would go to college, Baffert continued his education, but he gravitated back home soon after.

He trained horses for his father, but progress was slow. "I was really disgusted with it," he says, referring to his development as a trainer.

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Taking a year off, Baffert got a job as a teacher but that didn't work out either so he took up an offer to train some horses for a friend.

"I decided to give it one more go," he said. "I started winning and the next thing you know I've got five, 10, 15 horses and then I was going."

In 1983, Baffert moved to California to train at the famous Los Alamitos quarter horse track near Los Angeles.

"I was very intimidated because I knew how tough it was," he said. "I had 40 horses in Arizona and I took my best nine horses to L.A.

"I ran three horses the first night and I told a friend that if they don't do well I'm going back to Arizona.

"I was a big fish in a small pond there and now I was a little fish in a big pond. Luckily, the first one ran third, the next one ran third, and the third one won and that was it."

Bob Baffert talks to the media ahead of the 2019 Kentucky Derby at Churchill Downs.

'Heaven is in the winner's circle'

Baffert switched to training thoroughbreds, with a view to getting one to the Kentucky Derby.

"I bought some horses and gave myself three years," he said. "I won the Breeders' Cup Sprint [in 1992] with my first thoroughbred [Thirty Slews], which was so exciting. I really thought it was not going to get better than that."

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Turns out things got much better.

In 1996 he took a horse called Cavonnier to the Kentucky Derby at Churchill Downs. The Derby debutant had his heart in his mouth as Cavonnier took the lead halfway down the stretch.

"I thought he'd won, but he got caught and got beat an inch in the end," said Baffert. "It was a devastating loss. I just thought I'd blown my shot. For a year I was sort of depressed about it."

Fortunately for Baffert, he returned the following year with a grey colt named Silver Charm.

"He got the lead and there was another horse coming and I remember saying, 'Oh Lord, you can't do it to me again, I can't get beat again,'" he said. "I would have had to check myself into rehab or something."

Time stood still for Baffert as Silver Charm surged up the home straight. "I started thinking about my time as a quarter horse trainer and my mother saying, 'Why are you wasting your time training horses?'" he says.

Jockey Gary Stevens urged Silver Charm on and he held firm to give Baffert his first win on the biggest stage.

"It was the most incredible feeling you can have winning the Kentucky Derby," he said. "You're not really mentally prepared for it. It's the greatest race in America, with 150,000 people, Churchill Downs, the Twin Spires, it's just magical.

"If there's a heaven it's in that winner's circle. That's the most expensive piece of real estate in the world. It costs so much money to get into that small patch of grass but it's worth every penny of it."

Bob Baffert won the first of five Kentuck Derby titles with Silver Charm in 1997.

'Extraordinary'

Silver Charm also won the Preakness Stakes, the second leg of the fabled Triple Crown, but was second at the deciding Belmont Stakes to deny Baffert US racing's Holy Grail.

The following year, his charge Real Quiet achieved exactly the same feat, while War Emblem gave him a third Kentucky Derby in 2002 and American Pharoah triumphed in 2015 en route to the Triple Crown.

Baffert's latest success in the Kentucky Derby was with Justify as he clinched the first leg of his Triple Crown victory last year -- only the 13th horse ever to complete the trilogy.

"We didn't know how good he was but he found another gear that I didn't know he had," said Baffert. "That's what the great ones do.

"When he won the second race [the Preakness Stakes] I thought, 'Oh my goodness, this guy's the guy.'

"It's an incredible feeling for an owner or trainer to know they've got a superior race horse on their hands. You can tell when you have a really good one.

"American Pharoah, from day one we knew he was extraordinary. I felt a lot of pressure, I thought if I was ever going to win the Triple Crown, he was my last chance. I was so relieved when he won the Kentucky Derby. I thought, 'Ok, now we can start working on the next one.'"

Photos: 10 of the most picturesque racecourses Meydan Racecourse, Dubai – Boasting the world's first five-star trackside hotel, restaurants and a museum, Dubai's Meydan Racecourse is a first-class racing destination. Hide Caption 1 of 10 Photos: 10 of the most picturesque racecourses St. Moritz, Switzerland – St. Moritz is known for world-class skiing, glitz, glamor and...horse racing? The venue for the White Turf event, held three days a year, isn't your typical racecourse. Instead, it's held on a frozen lake. Hide Caption 2 of 10 Photos: 10 of the most picturesque racecourses Flemington Racecourse, Australia – Flemington is Australia's oldest metropolitan racecourse and home to the famous Melbourne Cup. The revamped venue was first used in 1840 when the town of Melbourne was just five years old. Hide Caption 3 of 10 Photos: 10 of the most picturesque racecourses Piazza del Campo, Italy – Simply put, there is no racecourse in the world quite like the Piazza del Campo in Italy. Its origins date back to medieval times when jockeys rode buffalo. The piazza is packed with spectators with racing around the outside. Hide Caption 4 of 10 Photos: 10 of the most picturesque racecourses Happy Valley, Hong Kong – Happy Valley Racecourse was built in 1845 to provide horse racing for expat Britons living in Hong Kong. It's surrounded by giant apartments and skyscrapers -- giving visitors an unusually beautiful scenic view. Hide Caption 5 of 10 Photos: 10 of the most picturesque racecourses Ascot, England – Just the name "Ascot" conjures visions of royalty, elegance, high fashion and world-class racing. The racecourse was opened in 1711 by Queen Anne, and Royal Ascot is still one of the most celebrated meetings on the calendar. Hide Caption 6 of 10 Photos: 10 of the most picturesque racecourses Chantilly, France – Spectacular and timeless, historic Chantilly sits in front of the 16th-century Chateau de Chantilly and the majestic Great Stables (pictured) amid forests 30 miles north of Paris. Hide Caption 7 of 10 Photos: 10 of the most picturesque racecourses Laytown Races, Ireland – Laytown Races is the only official beach race in Europe. Situated on the Irish coast, the 150-year-old tradition attracts more than 5000 regular visitors every year. Horses race along the sands on a makeshift course. Hide Caption 8 of 10 Photos: 10 of the most picturesque racecourses Goodwood Racecourse, England – The rolling Sussex countryside unfolds in front of one of the most iconic venues in flat racing. Goodwood has hosted racing since 1802 and offers the perfect setting for the famous Glorious Goodwood meeting. Hide Caption 9 of 10 Photos: 10 of the most picturesque racecourses Cheltenham Racecourse, England – Cheltenham is a shrine to jump racing against the idyllic backdrop of the Cotswold hills. It hosts the prestigious Cheltenham Festival every March, the highlight of the world's jump racing calendar. Hide Caption 10 of 10

'Running son of a gun'

The history of the Triple Crown is littered with great horses who fell short in the final race, but if there is any blueprint to follow, Baffert says you have to start with the raw ingredients -- a gifted athlete.

Then they have to have a "great mind" and "be able to handle the pressure," he says. Staying healthy is a must, and keeping their weight and strength up over the course of the five-week span between the Derby and the Belmont is also key. And lastly, they need large doses of luck.

"Stick to those five, but number one is most important," said Baffert.

"They've got to be a running son of a gun."

Photos: The Racing Post's Edward Whitaker shares his favorite images Photos: The Racing Post's Edward Whitaker shares his favorite images Supermoon – Multi award-winning snapper Edward Whitaker earned horse racing's photograph of the year award with this stunning image of a rare blue supermoon in Lambourn, Berkshire in January 2018. "I knew a spot where the angle was just right," he says. Here he talks CNN Sport through seven of his favorite images. Hide Caption 1 of 7 Photos: The Racing Post's Edward Whitaker shares his favorite images French fancy – Whitaker's image of French horse Arazi pulling off a stunning last-to-first victory in the 1991 Breeder's Cup at Churchill Downs made his name. "He went through the field like it was 'National Velvet' or some ridiculous film like that. I got this image of jockey Pat Valenzuela screaming his head off against the spires of Churchill Downs. My lot were blown away, it was a big breakthrough." Hide Caption 2 of 7 Photos: The Racing Post's Edward Whitaker shares his favorite images Shower time – Another picture that has defined his career is this shot of the great stallion Danehill being hosed down at Coolmore Stud in Ireland in 2003. "I just love the whole effect, how the water is reacting over the horse. He turns his neck so it was almost like a massage to him, and you can see how much he's enjoying it. I had to shoot it on a slow shutter speed and there's a real sense of movement in the water, and the light is just lovely."

Hide Caption 3 of 7 Photos: The Racing Post's Edward Whitaker shares his favorite images Kaleidoscopic – This color-filled image of Churchill Downs is another Whitaker favorite. "I knew there was this fire exit up to a door that opened onto the roof so I went up there and caught this great dawn. There was a cold front coming in, so I knew there would be some very dramatic reds and yellows in the sky. And now they light up the iconic spires with purple light, so the colors are unbelievable. It's so American and over the top." Hide Caption 4 of 7 Photos: The Racing Post's Edward Whitaker shares his favorite images Chantilly face – Horses break from the stalls in front of the Great Stables at Chantilly, France in 2016. "I love this shot because of the light and the horse rearing at the start. It's just a dramatic picture. That one horse going up gives it great strength." Hide Caption 5 of 7 Photos: The Racing Post's Edward Whitaker shares his favorite images Lucky horseshoe – Whitaker's luck was in with this picture from Cheltenham last January when he discovered the flying horseshoe. It was part of his portfolio that won an eighth photographer of the year award. "It was a remote picture from under the fence shooting into a clear blue sky. It was a nice picture anyway but the fact the shoe fell off and pointed upright was just unique. I'd never seen anything like it. That's why photography is so exciting." Hide Caption 6 of 7 Photos: The Racing Post's Edward Whitaker shares his favorite images Scared stiff – Whitaker conquered his fears and rode up in the TV crane to capture this image of the city of Chester and the racecourse. "This is the scariest picture I've ever taken. You go up on this wobbly plank with a safety harness clipped to a metal frame. I was absolutely terrified but the view was amazing, the light was just right and I got this great scene of Chester with the action on the racecourse." Hide Caption 7 of 7

So far Baffert's horses have won 15 American Classics and 15 Breeders' Cup races among more than 2,900 victories.

But for Baffert, training race horses is more a way of life than a vocation and opens doors to great friendships along the way.

"Trainers go to sleep thinking about our horses and we wake up thinking about our horses," he says.

"That's the beauty of it. We are working outdoors with these magnificent animals. It's the greatest therapy you can have. Whenever you're feeling down or depressed I just go to the barn and hang out with them.

"I'm so lucky that I found something I totally love.

"I'm the luckiest guy in the world."