Harry Russell, brother of former Clitheroe FC midfielder Charlie, caused an almighty shock when he was first past the post on rank outsider Astapor.
The 43-rated maiden, who is trained by Lancashire handler John Riches, hadn't won in 12 attempts beforehand, though had managed a third over a mile at Chepstow.
Having finished 10th when beaten by 27 lengths over 1m4f at Catterick the four-year-old Sixties Icon gelding was dropped drastically in trip to six furlongs and picked up the near £4,000 first prize.
Russell told Racing TV afterwards: "It's one of them things, it's racing. To be fair to Mr Richards he said he's a horse with plenty of speed. He travelled well and I never felt I was in any danger. He's gone away and won nicely.
"I couldn't feel anything coming, I was trying to glance at the big screen to see if anything was coming. Happy days!"
Astapor, who comfortably shrugged off the challenge of 8/15 favourite Parisiac, ridden by Graham Lee, had a Betfair SP of 1000 (999/1).
Betfair spokesperson, Barry Orr, said: "Although it’s not unique it is very unusual.
"Other notable winners to BSP at 1000 are most recently Sawbuck last month in Punchestown. Then you have to go back to 2010 when Maoi Chinn and Crianza both SP’d at the Exchange maximum, and Bermondsey Bob in 2008."