Trainer Jimmy Jerkens said Friday morning the quarter crack was discovered on the inside of the 3-year-old colts right front hoof Thursday after a morning gallop at Belmont Park.
Quality Road was broken and trained in Aiken by Legacy Stable's Ron Stevens.
Quality Road had a quarter crack to his right hind hoof after winning the Florida Derby last month, and it had completely healed, according to hoof specialist Ian McKinley.
The latest setback could knock Quality Road out of the Derby on May 2. Jerkens said the hoof wasnt sore, and that McKinley would look at the quarter crack later Friday. The trainer remains hopeful Quality Road can still make the Derby.
Quality Road is considered one of the Derby favorites, along with I Want Revenge and Pioneer of the Nile.