1943: three-year-old season
Because of the intensifying war effort, horse racing suffered many cutbacks starting in January 1943, including transportation restrictions and a shutdown of the Florida racing circuit. As a result, Count Fleet spent the winter at Oaklawn Park in Arkansas, then was shipped to Belmont Park, arriving on March 19. In early April, he kicked himself in a morning workout but shrugged off the injury with a strong workout on the following day, completing 1+1⁄8 miles in 1:55 despite being eased in the final eighth of a mile.
Count Fleet made his first start of the year on April 13 in the St James Purse over a sloppy track at Aqueduct. Going off at odds of 3:20, Count Fleet rated behind the early pace set by Bossuet, then started his move on the final turn to win by four lengths. Count Fleet was injured in the left foreleg during the race, but although the skin was broken he recovered quickly.
On April 17, Count Fleet returned in the Wood Memorial Stakes, going off as the 1-4 favorite. He was again injured, this time suffering a three-inch slice along the coronet band of a hoof, possibly caused when he was bumped at the start but more likely by a strike from one of his other legs as he started to accelerate. Count Fleet quickly entered into a duel with Blue Swords for the early lead, then was sent to the front on the first turn. He opened up a four length lead down the backstretch, then continued "serenely on his way" to victory.
After the race, the torn portion and part of the left hind hoof were removed, then the wound was packed with sulfa drugs. Fortunately, the wound did not become infected so Count Fleet was shipped on April 19 to Churchill Downs, which had to be done so soon after the Wood Memorial due to extensive travel restrictions.
The 1943 Kentucky Derby was almost not run because of wartime restrictions, but Colonel Matt Winn organized it as a "street-car Derby" – restricting travel for out-of-state residents and not allowing cars be driven to the event. Despite this, some 60,000 people attended the race and made Count Fleet the 2-5 favorite – the shortest starting price in Derby history. Ocean Wave, who would have been the second betting choice after winning the Blue Grass Stakes and Derby Trial, was scratched hours before the race. Count Fleet broke well and challenged Gold Shower, Burnt Shower and Blue Swords for the early lead. After a quarter mile, Count Fleet found himself boxed by the other horses but broke free moving into the first turn. He then moved up to challenge Gold Shower for the lead on the first turn and opened up a two-length lead down the backstretch. On the far turn, Blue Swords mounted a challenge and closed to within a length. Longden then clucked to Count Fleet, who quickly opened a three-length advantage and won handily.
"I never was afraid of Ocean Wave or any of the others in that field", said Longden. "I don't know the great horses like Man o' War because I wasn't around then. But the Count is the greatest I've ever ridden. Got everything, speed, heart – just everything."
Count Fleet again injured himself, this time in the left fore, but the injury was not serious. He shipped to Baltimore for the Preakness Stakes on May 8, going off as the 3-20 favorite in a four horse field. New Moon broke fastest but Count Fleet quickly took the lead and coasted to an eight length victory. His time was 1:573⁄5 for the distance of 1+3⁄16 miles over a track labeled as good, with the horses racing in the center of the track well away from the rail.
Count Fleet next entered the Withers Stakes at Belmont Park on May 22, cutting back in distance to a mile. Against only two rivals, he was made the 1-20 favorite. He seized the early lead and was never challenged while winning by eight lengths. His time of 1:36 over a slow track was the fastest mile of the meeting, despite the fact that Count Fleet raced more than 40 feet off the rail around the turn.
On June 5, Count Fleet completed the Triple Crown by winning the Belmont Stakes by 25 lengths (listed by The New York Times as 30 lengths). Going off at odds of 1:20 (the legal minimum) in a three-horse field, he led from start to finish. Despite the lack of competition, his time of 2:281⁄5 broke War Admiral's stakes record by two-fifths of a second. This time stood as the stakes record (though tied by Citation in 1948) until broken by Gallant Man in 1957. His margin of victory was also a record until broken by Secretariat in 1973, who won by 31 lengths.
After the race, his silks were auctioned for $50,000 in war bonds.
At the time, his sweep of the Triple Crown was considered "commonplace" as it had been done six times since Sir Barton in 1919. However, the victory earned Count Fleet favorable comparisons with Man o' War.
Once again, Count Fleet injured himself, this time by striking his left fore ankle early in the race. The ankle was X-rayed, indicating a slight wrench. Although it was believed that Count Fleet would soon return to racing, John Hertz released a statement in August that Count Fleet had subsequently developed a splint in his right foreleg that laid him up for two months. This effectively ended his three-year-old campaign, since it would take a further two months to get him back into racing shape. "We like him too well," said Hertz, "and we like racing and breeding too well, to attempt to force the training of this kind of horse and possibly start him in anything but his top condition."
With a record of six wins from six starts, Count Fleet was named the American Horse of the Year and champion three-year-old of 1943.