Haafhd returned to the scene of his 2,000 Guineas triumph to clinch the Emirate Airlines Champion Stakes at Newmarket on Saturday.
The three-year-old, trained by Barry Hills and ridden by son Richard, showed great stamina in a tough race.
Chorist looked as though she might hold on to win after taking the lead but Haafhd moved up strongly to push Kieren Fallon's mount into second.
Azamour, who was hoping to double up after his victory in the Irish Champion Stakes, finished in third.
Godolphin pacesetter Naheef combined with Chorist to set a blistering pace which strung out the field.
And pre-race favourite Doyen, ridden by in-form Frankie Dettori, never made a challenge.
But Haafhd pounded home untroubled, effortlessly finding an extra gear in his first race since the Sussex Stakes at Goodwood in July.
"He won a Guineas so I was never worried about how he would travel," said jockey Richard Hills.
"We were concerned about the ground but all the team rallied together, decided to run and it's great to win."
Mark Johnston's horse Mister Monet pulled up early on and left the course with a suspected fracture in a back leg.
Champion Stakes (1m 2f)
1 Haafhd (R Hills) 12-1
2 Chorist (K Fallon) 20-1
3 Azamour (M J Kinane) 6-1
Contact Dancer produced a late surge to land the marathon Totesport Cesarewitch Handicap at Newmarket on Saturday.
A clutch of horses drove for the line inside the final furlong but Royston Ffrench, who won the race back in 1996 on Inchcailloch, pushed the 16-1 shot home.
Joint-favourite Mr Ed also poured on the pace but had to settle for second place ahead of High Point with Quedex finishing in fourth place.
Theatre had taken up the lead from front-runner The Last Caste but Contact Dancer moved ahead two furlongs out and stayed on to win by half a length.
"My son Charlie said beforehand this horse would love the mud
and stay all day, and he was absolutely right," said winning trainer Mark Johnston.
Tote Cesarewitch (2m 2f)
1 Contact Dancer (R Ffrench) 16-1
2 Mr Ed (J Quinn) 10-1 Jt Fav
3 High Point (S Whitworth) 50-1
4 Quedex (C Haddon) 33-1
Shamardal proved he has returned to top form as he completed a successful day for trainer Mark Johnston in the Darley Dewhurst Stakes.
Kevin Darley held the two-year-old on a good line down the inside of the rail and he sprinted home to win by two-and-a-half lengths.
Aidan O'Brien's Oratorio also finishly strongly in second with Montgomery's Arch third.
Darley Dewhurst Stakes (7f)
1 Shamardal (K Darley) 9-2
2 Oratorio (J P Spencer) 15-2
3 Montgomery's Arch (M J Kinane) 10-1