First Avenue came from the clouds to cause a 20-1 surprise in the Paddy Power Imperial Cup to give Laura Mongan the biggest winner of her career.
With more in front of him than behind him as he turned into the straight some 15 lengths behind the runaway leader Kazlian, his young jockey Nathan Adams refused to panic.
Kazlian was still some five lengths clear when he crashed through the second last, losing his momentum and letting his challengers close the gap.
First Avenue was just hitting top gear then and powered away to win by three and and a half lengths from the staying-on Tanerko Emery with Kazlian tiring back in third and Barizan a game fourth.
Mongan said: "I was screaming pretty loudly coming to the last and just hoped he jumped it safe and sound.
"To win this is surreal.
"You've got to have a bit of confidence but we'd have been over the moon if he'd been placed. To win is incredible.
"This is my biggest win by some distance.
"Nathan gave him a smashing ride and knows him inside out."