2015: two-year-old career

Exaggerator began his racing career by finishing fifth behind Nyquist in a five-furlong maiden race at Santa Anita Park on June 5.^[9] On July 26 at Del Mar Racetrack Exaggerator started favorite for a maiden over six furlongs and recorded his first success, coming from well off the pace to take the lead in the final stride and win by a nose from Miner's Light.^[10] The colt was then stepped up in class for the Grade II Saratoga Special Stakes over six and a half furlongs at Saratoga Race Course. Racing for the first time outside California his final preparation for the race was handled by Desormeaux's assistant Julie Clark and he was ridden by Junior Alvarado. He raced at the rear of the six-runner field before producing a sustained run along the rail to take the lead inside the final furlong and won by three-quarters of a length from the favored Saratoga Mischief. After the race Clark commented that Exaggerator "showed some real class for a baby".^[11]

On October 3 Exaggerator started favorite for the Grade I Breeders' Futurity over eight and a half furlongs at Keeneland. After tracking the leaders he took the lead in the stretch but was overtaken in closing stages and finished second, beaten a length by Brody's Cause.^[12] Four weeks later, over the same course and distance, Exaggerator was one of fourteen colts to contest the Breeders' Cup Juvenile. After tracking the leaders he stayed on in the stretch without ever looking likely to win and finished fourth behind Nyquist, Swipe and Brody's Cause, beaten three lengths by the winner. On his final appearance of the season, Exaggerator started favorite for the Delta Downs Jackpot Stakes run on November 21 on a muddy track at Delta Downs in Louisiana. The best fancied of his rivals was Sunny Ridge, who had finished runner-up in the Champagne Stakes. Exaggerator took the lead after a quarter mile and fought off a sustained challenge from Sunny Ridge to win by a neck. Commenting on the colt as a potential Kentucky Derby contender Keith Desormeaux said "He's bred for it. He has the precociousness and the athleticism for it."^[13]

2016: three-year-old career

Exaggerator winning the Preakness

Exaggerator began his second season in the Grade II San Vicente Stakes at Santa Anita on February 15. He came from off the pace and finished strongly but was beaten one and a half lengths into second place by Nyquist. Up to this point the colt tended to run as a "stalker", staying close to the pace. After the San Vicente, Desormeax changed tactics and began training him to colt fall back and come from behind, making him a "closer".^[6]

In the San Felipe Stakes on March 12 Exaggerator started second favorite behind Mor Spirit, a Bob Baffert-trained colt who had won the Los Alamitos Futurity and the Robert B. Lewis Stakes on his last two starts. He challenged for the lead on the final turn but finished third behind the wire-to-wire winner Danzing Candy with Mor Spirit taking second. Exaggerator faced Danzing Candy and Mor Spirit again in the Grade I Santa Anita Derby on April 9 and started third choice in the betting at odds of 3.4/1. Racing on a sloppy track, Exaggerator trailed the field in the early stages as Danzing Candy set the pace but began to make rapid progress half a mile from the finish. He drew alongside the leaders on the final turn and quickly went clear of the field to win by six and a quarter lengths from Mor Spirit with Uncle Lino taking third ahead of the tiring Danzing Candy. Kent Desormeaux commented "He was the fourth horse that I rode in the mud today and the others felt like they had ice skates on: Exaggerator felt like he had track shoes on. He really liked the going and I think that was part of his incredible effort today. He enjoyed the mud".^[14]

On May 7 Exaggerator started second favorite in a twenty-runner field for the 2016 Kentucky Derby. Racing on a fast surface he was towards the rear of the field until he began to overtake horses in the last half mile. He made a strong challenge in the straight but was unable to overhaul the favored Nyquist and finished second, beaten one and a quarter lengths.^[15] On May 21 Exaggerator started second favorite behind Nyquist for the Preakness Stakes at Pimlico Race Course, with the lightly raced Stradivari the best-fancied of the other nine runners. On a rainy day, and a sloppy but sealed track, Kent Desormeaux restrained the colt well behind the very fast pace set by Nyquist and Uncle Lino. Exaggerator began to make progress on the inside approaching the final turn before being switched to the outer to make his challenge in the straight. He overtook Nyquist approaching the final furlong and drew away in the closing stages to win by three and a half lengths. The outsider Cherry Wine, who had hit his head on the starting gate and was second-to-last for much of the race finished strongly to deprive Nyquist of second by a nose.^[16] After the race the winning jockey commented "I had a dream trip today. I was on the fence and they all stayed wide. With these turns you want to paint the fence. We did, they didn't... knowledge is power". Explaining the colt's light training regimen since the Derby, Keith Desormeaux said: "My philosophy was to take it as easy as possible because you're not going to gain any fitness in those two weeks. I did what I could to get him happy and fresh and strong".^[17]

After an 11th-place finish in the G1 Belmont Stakes on June 11 Exaggerator returned to the races in the G1 Haskell Invitational at Monmouth Park on July 31. Over a sloppy track, Exaggerator bested American Freedom to win the race in a final time of 1:48:70.^[18] "It was a reminder of the Preakness. … I just tried to bide my time", Desormeaux said after trailing by 8 1/2 lengths at the half-mile pole. "He really exploded at the quarter pole … rode right off my fingertips. Exceptional race horse."^[19] In the Travers Stakes on a fast track at Saratoga on 27 August Exaggerator started favorite but was never in contention and finished eleventh of the thirteen runners behind Arrogate.