[5] For his next start, Maxfield was stepped sharply up in class in the Grade I Breeders' Futurity Stakes at Keeneland on October 5.
[6][7] The victory made Maxfield one of the early favorites for the 2019 Breeders' Cup Juvenile, but he was withdrawn from the race after he started favoring his right foreleg following a workout.
Despite the layoff, he went off as the 7-5 favorite in a field of ten that included multiple Derby hopefuls such as Ny Traffic and Pneumatic.
He split between horses on the turn to find racing room, then battled with Pneumatic and Ny Traffic down the stretch.
He was sent to Rood and Riddle Equine Hospital where Dr. Larry Bramlage inserted a couple of screws to stabilize the leg while it healed.
Breaking more alertly than in the past, he defeated Pat Day Mile runner up Sonneman by 2+1⁄2 lengths in his fourth consecutive win.
[12][13] Maxfield began his four-year-old campaign on February 13, 2021 in the Mineshaft Stakes at the Fair Grounds, where he kept his undefeated record intact with an easy 3+1⁄4 length victory over Sonneman despite again breaking poorly.
After settling mid pack he cleared the field with a furlong to race and continuing to increase his margin of victory to 3+1⁄4 lengths in a time of 1:48.53.
[18] After anonther eight week break Maxfield was entered in the Grade I Woodward Stakes, which was moved to Belmont Park in 2021.
Maxfield started as the 9-10 odds-on favorite, broke evenly and settled behind the leaders, but pinned in down on the rail.
"[19] In his last start of his career in the Grade I Clark Stakes at Churchill Downs Maxfield was almost an equal favorite at 6/5 with Midnight Bourbon.