Newmarket trainer Charlie Fellowes will aim to add the U.S. to the list of countries where he has saddled winners when lining up Luther in the July 4 Belmont Derby Invitational Stakes (G1T).

Two-year-old thoroughbreds flashed past him, hooves thundering down the rail. He turned to the railbirds and half-jokingly told them, "One day, I'll just roll off this pony onto the track and let the ...