Square Eddie, one of last year’s top 2-year-olds whose 3-year-old campaign was interrupted when he suffered a stress fracture to his left front leg in February, was withdrawn from the Kentucky Derby yesterday when trainer Doug O’Neill felt some heat in his left front shin.

“X-rays didn’t show anything, but Dr. (Mark) Cheney said it might not be best to take any chances,” O’Neill said. “We decided to err on the side of caution.”

That opened a spot in the 20-horse field for Atomic Rain, fourth last out in the Wood Memorial, who was loaded on a van at Monmouth Park yesterday afternoon.

“It’s about a 13-hour trip,” trainer Kelly Breen said. “They should get here about 2 in the morning.”