Maximum Security, ridden by Luis Saez, took victory in the inaugural Saudi Cup.
The US-trained 6-5 favourite stormed to the front with half a furlong remaining of the world's most valuable race, worth $20m (£15.5m) overall.
Another American runner, Midnight Bisou, came second with a stunning finish and Benbatl claimed third.
Maximum Security had previously been controversially disqualified after winning the Kentucky Derby in May 2019.
There was a crowd of about 10,000 at King Abdulaziz Racecourse to witness what was an epic first running of the nine-furlong race on a dirt track.
Maximum Security had won two Grade One races since the Kentucky Derby and put in a gutsy display to make up for that disappointment.
"He came here and showed he is the best," said winning jockey Saez. "This is amazing, I can't tell you how it feels.
"When we broke [from the stalls] he didn't grab the bridle like he used to, but that was OK - when we came into the stretch he wanted to win, he wanted to fight."
A redemptive victory looked unlikely for much of the contest as Pegasus World Cup winner Mucho Gusto travelled strongly.
He took a few lengths out of the field before beginning to wander under Irad Ortiz Jr close to home, eventually finishing fourth.
Dettori rides Dark Power to shock 66-1 victory
Seven races were run earlier in the day in Riyadh, with prizes worth another $9.2m (£7.2m).
Frankie Dettori provided one of the highlights, riding Dark Power to a shock 66-1 victory in the stc 1351 Cup.
The Italian jockey timed his run to perfection to go past Mubtasim in the dying strides.
Trained in Bahrain by Allan Smith, the grey took his form to a new level with some quality horses left trailing in his wake.
Glorious Journey also made good late headway to finish third.
Dettori said: "Sheikh Isa [owner] is a friend of mine. I've been going to Bahrain for the last five years and I took the ride a month ago.
"I didn't know what to expect to be honest with you, but this is an amazing feeling.
"To win a race like this for your mates is a double whammy."