Six years ago, Hall of Fame trainer Bill Mott’s victory in the Kentucky Derby didn’t start with cheers and hugs, but silence and suspense.  Saturday at Churchill Downs, the joy was instant thanks to Sovereignty’s dominant performance at the 151^st Kentucky Derby.

In 2019, Mr. Mott had to wait through a tense 24-minute review before celebrating. Stewards at Churchill Downs took that long before ruling that Maximum Security, who crossed the finish line first, had interfered with other contenders, elevating Mr. Mott’s horse, Country House, to the winner’s circle.

Country House was awarded the coveted garland of roses and all the pageantry that comes with winning the first leg of the Triple Crown. But it was a Derby win wrapped in controversy, a triumph without the electrifying moment of watching his horse thunder home first.

Fast-forward to Saturday at rain-soaked Churchill Downs, and there was no need for replays, rulings, or asterisks. This time, the joy was instant as Sovereignty surged down the homestretch, overtaking the heavily favored Journalism to claim a definitive victory before a crowd of 147,406.

“He made up a lot of ground in a hurry,” Mr. Mott said of Sovereignty, who stormed past Journalism, the betting favorite, to win by a length and a quarter. “He’s a great horse. I can’t say enough about the horse and the organization that started him out.”

Rain left the track wet and muddy, conditions under which most of the horses had never experienced. “Nobody knows how their horses are going to run on this track,” Mr. Mott had said earlier in the day.

Starting from post No. 18 in the 19-horse field, Sovereignty was a 7-1 choice with betters respecting the closing speed he displayed in winning the Fountain of Youth and finishing second in the Florida Derby.

Jockey Junior Alvarado orchestrated the race of his life a few weeks after being hospitalized with a hairline fracture in his right shoulder after falling off his horse during a race at Gulfstream Park.

Mr. Alvarado of Venezuela let the Bob Baffert entry Citizen Bull set the early speed and waited until the top of the stretch before making a strong move to thunder past the leaders. With a furlong to run, it was a two-horse race between Sovereignty and Journalism, winner of four straight races. With 100 meters left, Sovereignty started pulling away.

“This means the world to me,” Mr. Alvarado said. “Mr. Mott was so confident all week. We’ve been a team for a while. It’s more than a dream come true to have done it with him.”

Baeza, a late entry after two horses, Rodriguez and Grande, scratched and finished third with Final Gambit fourth.

Mr. Mott, regarded as the best trainer for racing on turf in the United States, enjoyed winning the Derby in 2019. But winning without controversy offered an exclamation point.

Next up is the Preakness in two weeks, where Sovereignty is the only horse in the field with a chance to win the Triple Crown, though Mr. Mott wasn’t ready to confirm his horse will be entered at Pimlico Race Course.

“The pressure is on now to go,” Mr. Mott said. “We’ll talk with the team and make a joint decision and try to do the right thing.”