When Todd Pletcher made his Triple Crown debut in the 2000 Kentucky Derby, his oldest child was a baby. Seventeen years later, Pletcher has five trophies from the 3-year-old classics and his son Payton is about to graduate from Garden City High School.

“It’s flown by,” Pletcher said the morning after his gray colt Tapwrit rallied to win Saturday’s 149th Belmont Stakes by two lengths. “I think sometimes you start to reflect when you see your kids growing up.

“The other day I was walking back to the barn and thinking about 1995, when I was working for Wayne [Lukas] and we won the Belmont with Thunder Gulch.”

Unless he sweeps the Triple Crown, Pletcher never will have a spring as rewarding as this one. Always Dreaming gave him his second Derby victory, and Tapwrit was his third winner of the 1 1⁄2-mile “Test of the Champion” in his backyard, Belmont Park. Two out of three ain’t bad, it’s terrific.

Not that there weren’t some very low moments. After dominating at Churchill Downs, Always Dreaming was full of energy at Pimlico, and Pletcher figured he could return to Belmont with a shot at a sweep.

Vinnie Viola, one of Always Dreaming’s owners, asked Pletcher if he would enter Tapwrit in the Belmont if Always Dreaming won the Preakness. Pletcher teased the billionaire West Point graduate, who in February turned down President Trump’s offer to become secretary of the Army.

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“I told Vinnie we would try not to,” Pletcher said, “but that he might have to pay a hefty price for Tapwrit.”

That scenario never developed. Pletcher was seriously bummed out when Always Dreaming faded to eighth in the Preakness after dueling with Classic Empire.

“The Derby win was awesome, and the ebbs and flows of this game are well documented,” Pletcher said Saturday. “The last five weeks have been the ultimate roller coaster for us.’’

So have the last 18 springs, in which Pletcher has been a major player on the three Saturdays when millions fixate on thoroughbred racing. There was the joy of his Triple Crown breakthrough with the filly Rags to Riches in the 2007 Belmont and his first Derby win with Super Saver in 2010. There was the relentless criticism for saddling the most losers (46) in Derby history. That journalistic rite of spring is on hold for the foreseeable future.

“It’s been fun,” Pletcher said before adding “sometimes” with a wry smile.

As the leading money-winner of all time and a lock for the Hall of Fame, Pletcher is expected to win. When you get the best-bred and most expensive yearlings, the pressure to develop 3-year-old stars never lets up.

“The Triple Crown is an interesting five weeks for us,” he said, “and before that are the months leading up to the Derby. There’s a lot of anxiety and ups and downs.’’

This year, for the first time, the highs outweighed the lows. Pletcher’s father and first mentor, J.J. Pletcher, runs a training center in Ocala, Florida, where he prepares many of Todd’s young horses.

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“Two-thirds of the Triple Crown,” J.J. Pletcher said with satisfaction. “We thought this horse had a big chance. Everybody that called to ask, I told them to bet Tapwrit.”

J.J and Wayne Lukas have been pals since the Sixties, when they trained quarter horses in the Southwest. Lukas, the all-time leader with 14 Triple Crown wins, didn’t win his fifth until 1995, when he was almost 60. Todd Pletcher turns 50 June 26, a milestone birthday. With his seemingly endless supply of quality horseflesh, his old boss’ milestone might not be out of reach.