Accelerate's dam, Issue, was sired by Breeders' Cup Classic winner Awesome Again and descends on the female side from Kentucky Broodmare of the Year Smartaire.
He made his next start in the inaugural running of the mile Shared Belief Stakes on August 26 at Del Mar.
He ran in third position most of the race, before taking the lead on the final turn and holding off Taman Guard and Semper Fortis to prevail by half a length.
Sitting in fourth position and wide throughout the race, he made a move on the final turn to challenge Blackjackcat, as Semper Fortis took the advantage on the rail.
[5] Accelerate trained for his first attempt in a grade I race, the Breeders' Cup Dirt Mile on November 4 at Santa Anita.
[7] Accelerate started his 4-year-old season in the GII San Pasqual Stakes on January 1 at Santa Anita Park, where he finished second on a sloppy track, 1+1⁄4 lengths behind the favorite, Midnight Storm.
He had a 7-length lead as he entered the homestretch, and widened the margin to 8+1⁄2 lengths as he passed the wire, as Arrogate finished far back in fourth.
[13] His trainer, John Sadler, said after the race: "He trained really well Sunday up at Santa Anita and showed a lot of pop when Victor worked him from the gate, and they kept telling me it was $50,000 for second.
On July 29, Sadler announced that Accelerate would run for the first time at the distance of a mile and a quarter, and would have a rematch with Arrogate in the GI Pacific Classic Stakes on August 19 at Del Mar Racetrack.
He settled in third position and stalked throughout the race, and ran evenly in the stretch to hold second place, beaten 3+1⁄4 lengths by multiple-graded stakes winner Giant Expectations.
Mubtaahij, ridden by Drayden Van Dyke, moved onto the rail and forced Accelerate to be checked back.
[24] He broke well, and moved up to third, with Malibu Stakes and Triple Bend Handicap winner City of Light sitting directly behind him.
City of Light pulled a length in front, but Accelerate continued to battle from the inside to close the margin to a neck.
[27] He was entered to defend his title in the GII San Diego Handicap on July 21 at Del Mar, but he was scratched since John Sadler did not want to run his stablemate, Catalina Cruiser, and Accelerate in the same race.
Then Accelerate shipped outside of California for the second time in his career to run in the GI 1+1⁄4 Breeders' Cup Classic on November 3 at Churchill Downs.
[34] Accelerate arrived at Lane's End Farm on November 4 for a brief break and to be available for inspection by breeders before training for his final start in the GI 1+1⁄8-mile Pegasus World Cup on January 26.
[38] After standing five seasons at stud, Accelerate failed to get a big runner and was pensioned from stallion duty, relocating to the Kentucky Horse Park in Lexington to reside at the Hall of Champions.