After announcing his arrival in August by winning the 147-year-old Travers Stakes in a track-record time, the colt then pipped the much-loved California Chrome at the last in November's epic Breeders' Cup Classic.
In London Tuesday, the horse -- owned by Saudi Arabia's Prince Khalid bin Abdullah -- was named the best in the world.
Arrogate, trained at Kentucky-based Juddmonte Farms, beat Chrome and Australian wonder-mare Winx to the 2016 Longines World's Best Racehorse award.
"It's remarkable, it really is," Juddmonte's delighted racing manager Teddy Grimthorpe told CNN after the plush ceremony at Claridge's Hotel.
"It's a great result for Juddmonte and for Prince Khalid to have his horse recognized."
Breeders' Cup Classic drama
As a three-year-old, Arrogate won five successive races in 2016 after finishing third on debut at Los Alamitos in April.
The victory at the Breeders' Cup Classic -- which was again named the top-rated race of the year at the Longines ceremony -- was enough to give Arrogate a ranking of 134 compared to 2014 Kentucky Derby winner Chrome's 133 and Winx's 132.
The World's Best Racehorse rankings, upon which the award is based, are established by international handicappers according to the performance of horses in elite races.
Winx won all eight races in 2016 as a five-year-old, taking take her unbeaten streak to 13 in a row, and was the highest rated turf horse.
November's Breeders' Cup defeat was the only time Chrome was beaten in eight starts in 2016.
The American five-year-old will meet Arrogate again at Saturday's Pegasus World Cup Invitational, which will be Chrome's final appearance before retiring.
Grimthorpe believes another titanic battle is on the cards.
"You can't have good horses that don't meet good horses," the British peer said. "In terms of the Breeders' Cup Classic, you say it was Arrogate and California Chrome. I suspect that Saturday's race will probably turn out that way as well, whatever way it goes."
Arrogate still improving
Arrogate's renowned trainer Bob Baffert was similarly complimentary of what will likely be his charge's main rival at the $12 million event in Florida.
"He's been such a fan favorite and he's been great for racing," Baffert told reporters of Chrome, which also won the Preakness Stakes in 2014 but could not complete the Triple Crown, finishing fourth at the Belmont Stakes.
"He went to Dubai and won all year long," he said, referring to Chrome's triumph at the 2016 Dubai World Cup.
But the 64-year-old Baffert -- who also trained 2015 Triple Crown winner and that year's Longines World's Best Racehorse, American Pharoah
-- believes Arrogate will only improve in the coming months and years.
"He starting to show me things that American Pharoah was showing me," Baffert added. "He will get better."
His next test comes Saturday.