A winner for Mick Channon at the track in January, he scraped into the race as the 20th of the 20 runners.
Settled in mid-division, Mister Whitaker's backers would not have been getting their hopes up as Rocklander led over the last, only for Jerry McGrath to sweep by on Rather Be.
Hughes had just managed to save a bit on Mr Whitaker (13-2), however, and in a driving finish, managed to come out on top by a head.
Rocklander was just over three lengths back in third, with the well-fancied Barney Dwan fourth.
Henrietta Knight, who trained Best Mate to win three Gold Cups, bought the winner for Tim Radford, whose company Timico sponsor Friday's Gold Cup.
"It's so fantastic. It's the first horse I bought for Tim since Terry (Biddlecombe) died and it's such a thrill," she said.
"I know the feeling, I know the atmosphere. It's just magic. Brian was just perfect with him.
"I first saw this horse at the Costellos, the same place I bought Best Mate from. I saw him jump and I just loved the horse.
"He wasn't too expensive and he's such an athlete."
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