The $30,000 purchase only made the field for the Grade 1 showpiece on Friday when Ethereal Road was scratched by Hall of Fame trainer D Wayne Lukas but stormed to victory with a late burst of acceleration in an upset over favourite Epicenter in second place and Zandon in third.
The chestnut colt's win will go down as the second biggest upset in the race's history, following Donerail at 91/1 in 1913.
The lightly-raced three-year-old's best previous finish in a Stakes came when finishing third in the Jeff Ruby Steaks at Turfway Park in April.
Trainer and Kentucky native Reed said victory by three-quarters of a length was a dream come true.
"I fell down in the paddock when he hit the wire," he said.
"I passed out. I'm so happy. This is the reason everybody does this.
"We're not supposed to be here but I knew this horse loved this track and he has been training so good all year."
Rich Strike ran one and a quarter miles in 2:02.61s and the victory was made all the more remarkable given that jockey Sonny Leon had to come through the 20-horse field.
"We always felt like if we could just get into the race, we'd have a shot, and we proved it today," owner Rick Dawson for RED TR-Racing LLC told reporters.
"We've never entered a race we didn't think we could win. Ever."
A jubiliant Sonny Leon told reporters: "Well I'm feeling really happy, you don't know how excited I feel. I brought all my family with me, my daughter's first time at the Kentucky Derby, the first time for me and we did it."
"It was amazing - amazing, especially the way we did it, in the last 50 yards, it's a dream come true."
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