(CNN) American Pharoah sat back in the starting gate and when the doors opened he was late. For a moment, for one second out of 146, it didn't look good for the horse who was chasing history.

But the 3-year-old bay colt, bidding to become the 12th horse to win the Triple Crown and the first in 37 years to win it, burst to the front and took control of the small, eight-horse field and his destiny.

The Belmont Stakes was over before anyone watching the race knew. That is except for trainer Bob Baffert. He and jockey Victor Espinoza understood how great their horse is and, even before the Belmont was halfway done, they were certain they were going to win.

"Down the backside he was in his groove and I knew he's a great horse and he was going to do it," Baffert said. "He's just a great horse. It takes a great horse to do (win the Triple Crown)."

The trainer later said: "I could tell by the eighth pole it was going to happen and all I did was just take in the crowd. It was thundering."

American Pharoah is the first Triple Crown winner since Affirmed won the Kentucky Derby, Preakness Stakes and Belmont Stakes in 1978.

Owner Ahmed Zayat, when handed the Triple Crown trophy, said: "I am so thrilled, honored, privileged, humbled, excited."

American Pharoah was the only horse in the race who had run both the Kentucky Derby and the Preakness. But he showed early he didn't have tired legs.

The odds-on favorite started from the fifth post and was slow out of the gate, but given daylight to his inside, he was in the lead before the first pole.

He set a moderate pace, with five of the other seven horses just behind.

Espinoza sensed history early in the race.

"In the first turn it was the best feeling I've ever had," he told reporters.

To the 90,000 fans at Belmont Park, the 1 1/2-mile race was still among a tight group of a half dozen horses. They stayed bunched down the backstretch with American Pharoah slightly ahead.

As he came out of the far turn, he motored to a two-length lead. Finally, the crowd could sense the drought was about to end and roared their approval. American Pharoah wears ear plugs, but the people in the stands were so loud he just might have heard them.

American Pharoah kept extending the lead until crossing the finish line in 2:26.65, the sixth-fastest time in Belmont history.

Photos: Triple Crown winners Photos: Triple Crown winners Kentucky Derby and Preakness Stakes winner American Pharoah wins the 147th running of the Belmont Stakes in New York on Saturday, June 6, to become the first horse to win the Triple Crown since Affirmed did so in 1978. Hide Caption 1 of 12 Photos: Triple Crown winners Sir Barton was the first horse to earn the Triple Crown of Thoroughbred Racing, as it would come to be known, by winning the Kentucky Derby, Preakness Stakes and Belmont Stakes in 1919. Hide Caption 2 of 12 Photos: Triple Crown winners More than a decade later, Gallant Fox captured the Triple Crown in 1930. Hide Caption 3 of 12 Photos: Triple Crown winners Jockey Pat Beasley rides Omaha in 1936. The horse won the Triple Crown in 1935. Hide Caption 4 of 12 Photos: Triple Crown winners War Admiral won the Triple Crown in 1937. He won 21 of his 26 career starts. Hide Caption 5 of 12 Photos: Triple Crown winners Whirlaway, right, won the Triple Crown in 1941. Hide Caption 6 of 12 Photos: Triple Crown winners Count Fleet, who won the Triple Crown in 1943, is adorned with flowers after winning the Preakness that year. Hide Caption 7 of 12 Photos: Triple Crown winners Assault won the Triple Crown in 1946. Hide Caption 8 of 12 Photos: Triple Crown winners Citation won the Triple Crown in 1948. Hide Caption 9 of 12 Photos: Triple Crown winners Secretariat, left, heads to victory at the Kentucky Derby in 1973. Considered by many to be the greatest racehorse of all time, Secretariat still holds the record for the fastest times in all three Triple Crown races. He won the Belmont by an astounding 31 lengths. Hide Caption 10 of 12 Photos: Triple Crown winners Jockey Jean Cruguet guides Seattle Slew to the Triple Crown in 1977. Hide Caption 11 of 12 Photos: Triple Crown winners Jockey Steve Cauthen rides Affirmed to a Belmont victory in 1978. Hide Caption 12 of 12

'Special horse'

Baffert said his horse had trained very well and the team had him prepared to win.

Baffert and Espinoza each won their first Triple Crown after multiple prior attempts with other horses.

"I just feel like I have a very special horse and he's the one that won," Baffert, 62, said. "It wasn't me."

Baffert had been frustrated three times before but none was more upsetting that 1998 when his horse Real Quiet dueled with Victory Gallop. Real Quiet won the Derby and the Preakness, and he led the Belmont at the start of the long homestretch. Victory Gallop made up significant ground and won at the wire by a nose.

"I was really getting to dislike this trophy. It's caused me a lot of misery," Baffert said. "I still can't believe it happened. ... I couldn't be any happier."

Third time a charm

Espinoza, 43, also had a record-setting day as the oldest jockey to win the Triple Crown. He is also the first Latino jockey to win it.

"I came here with a lot of confidence, more confidence than the last two (Triple Crown attempts)," he said. "That trophy it caused me a lot of stress ... but the third time was the charm."

Photos: American Pharoah wins the Triple Crown Photos: American Pharoah wins the Triple Crown Kentucky Derby and Preakness Stakes winner American Pharoah wins the 147th running of the Belmont Stakes on Saturday, June 6, in New York to become the first horse to win the Triple Crown since Affirmed did so in 1978 Hide Caption 1 of 7 Photos: American Pharoah wins the Triple Crown The 3-year-old bay colt led wire-to-wire and defeated second-place Frosted by a comfortable margin. Hide Caption 2 of 7 Photos: American Pharoah wins the Triple Crown Victor Espinoza looks back after crossing the finish line. Hide Caption 3 of 7 Photos: American Pharoah wins the Triple Crown American Pharoah leads the field entering turn three. Hide Caption 4 of 7 Photos: American Pharoah wins the Triple Crown American Pharoah leads Materiality and the rest of the field down the backstretch. Hide Caption 5 of 7 Photos: American Pharoah wins the Triple Crown And they're off! Until Saturday, 13 horses since 1979 had won at Churchill Downs and Pimlico but failed to triumph at Belmont.

Hide Caption 6 of 7 Photos: American Pharoah wins the Triple Crown American Pharoah is led to the starting gate ahead of the race. Hide Caption 7 of 7

Espinoza first competed for the Triple Crown in 2002, but War Emblem faltered and finished eighth at Belmont. California Chrome finished fourth in 2014.

Until Saturday, 13 horses since 1979 had won at Churchill Downs and Pimlico but failed to triumph at Belmont.

In 1978, Affirmed, ridden by Steve Cauthen, defeated second-place Alydar in three exciting races.

Triple Crown winners

1919 -- Sir Barton

1930 -- Gallant Fox

1935 -- Omaha

1937 -- War Admiral

1941 -- Whirlaway

1943 -- Count Fleet

1946 -- Assault

1948 -- Citation

1973 -- Secretariat

1977 -- Seattle Slew

1978 -- Affirmed

2015 -- American Pharoah