European raiders Magician and Side Glance had to settle for the place prize-money as Hardest Core caused a turn-up in the Arlington Million.
Jamie Spencer and Side Glance enjoyed an uncontested advantage in the early stages and Spencer was able to set ideally slow fractions aboard his mount.
But Joseph O'Brien had Magician sat handily in second and turning for home, the pair were locked together battling it out.
Under a hard ride from O'Brien, Magician put his head in front and looked as if he was going to score until outsider Hardest Core - available at 40/1 with British bookmakers earlier in the day but sent off at 11/1 on the local Tote - came surging down the outside of the pack.
Steadily reeling in the winner under the unheralded Eriluis Vax, Hardest Core hit the front 75 yards from the finish to win going away by a length, with a further length and a quarter back to Side Glance, whose trainer Andrew Balding was hitting the frame for the second time at the meeting after Havana Beat's earlier third in the American St Leger.
The winner earned a guaranteed berth in the Breeders' Cup Turf, this being a 'win-and-you're-in' qualifier. Winning trainer Eddie Graham had never even entered a horse in a Graded race before, let alone tasted victory.