[1] He started his three-year-old campaign on January 13, 2018 in a maiden special weight race at Oaklawn Park, finishing second.
[1] On February 3, he entered another maiden race at Oaklawn, in which he led from the start and opened up in the stretch to win by 10 lengths.
[3] He earned a strong Beyer Speed Figure of 96 in the race, but Asmussen decided to keep the colt to sprint distances rather than test him on the Triple Crown trail.
In a change of tactics, Mitole rated in third behind Promises Fulfilled and Bobby's Wicked One, who completed the first half mile in a fast :44.71 seconds.
Mitole pressed the early pace set by Coal Front, moved to the lead at the head of the stretch and held off a late run from McKinzie to win by three-quarters of a length.
"[11] Mitole's seven-race winning streak was broken in the six furlong Alfred G. Vanderbilt Handicap on July 27 at Saratoga Race Course, when he finished third to Imperial Hint.
[12] He rebounded in the Forego Stakes on August 24, in which he vied for the early lead with Promises Fulfilled then pulled away in the stretch to win by three lengths.
"I think the circumstances for the Vanderbilt just didn't suit him – coming off a huge run in the Met Mile and cutting back to three-quarters," said Asmussen.
Ned Toffey, the general manager of Spendthrift, commented that the colt's brilliance was best illustrated by his win in the Metropolitan Handicap.
Mitole settled a few lengths behind while racing wide, then started to make up ground as they rounded the final turn.
Shancelot still had a narrow lead in mid-stretch but Mitole drew away in the final furlong to win by 1+1⁄2 lengths in a time of 1:09.