Cherry Wine was second, while Nyquist finished third. The winning time for the 1 and 3/16-mile run was 1:58.31.
"I'm in shock right now," said Desormeaux, who has won seven Triple Crown races. "I had a dream trip today."
The jockey said the key to victory was Exaggerator's ability to run near the inside fence while the other horses took a wider path.
"These turns, you want to paint the fence," he said.
The track at Pimlico Race Course in Baltimore was very muddy, thanks to a cold rain that fell all day.
It's the latest achievement for arguably the greatest marathon runner in history -- his time of two hours, two minutes and 37 seconds is the second fastest marathon of all time.
The rest of the field simply couldn't handle the pace as Kipchoge put his foot down at the halfway mark and then again with just over a mile left to run.
His time was slightly off his own world record pace of two hours, one minute and 39 seconds -- which he set at the Berlin Marathon in 2018.
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