The Charlie Appleby-trained colt was rated 89 back in April yet he has gone up 25lb in the ratings and picked impressive prizes such as the Group Three Jersey Strakes at the Royal meeting.
The Dubawi gelding had run with credit in both the July Cup and Haydock Sprint Cup without making the frame, but that experience in Group Ones was a positive - as was the stiff six furlongs on soft ground.
Last year's winner Glen Shiel made the running and proved a tough nut to crack, but Creative Force (11-2) was up to the task.
Hitting the front in the final furlong, the Godolphin runner kept up the gallop to hold off Glen Shiel (22-1) by a length and give Buick his 151st winner of the season, two behind reigning champion Oisin Murphy with just four races left on the final day of the title race.
Minzaal (16-1) was a length back in third with Art Power (3-1 favourite) a head away in fourth.
Appleby, remarkably saddling his first Champions Day runner, said: "After Haydock, it was always the plan to come here. The two positives were the ground being what it is and secondly him sharpening up.
"After winning the Jersey here at the Royal meeting, we ran him in the July Cup and then backed him up at Goodwood. James (Doyle) said he over-raced at Goodwood and felt like a sprinter in a seven-furlong race.
"I thought we were going to run a big race at Haydock, but the ground was too fast for him.
"In these big sprints they've got to be able to travel and this horse travels for fun. William rode him with bags of confidence and having won over seven here, we knew he was going to hit the line hard.
"It's a great team result. It's been a great season and for this little horse to win a Group One is brilliant.
"He's a typical Dubawi who should get better with age and I feel the sprinting division is quite open.
"With Starman retired, there's a hole there to be filled and I feel this horse is potentially young enough to do that - we've been looking for a new star sprinter since Blue Point was retired, so hopefully this horse can be a fun horse for the next year or two."
It was ultimately not to be for Buick in his absorbing tussle with Murphy, but he said of his winner: "He really did deserve it. Obviously he won the Jersey here and he goes through that ground, which is a big help.
"The race worked out perfectly today - we had a nice draw and I liked the look of it. It worked out how I wanted it to and he was in good form going into it.
"He certainly deserved it, but we thought it was a good chance for him to show his best today.
"There were a lot of runners, they all turned up but he travelled into it very smoothly and it was a case of just waiting with him a little bit.
"He stumbled out of the stalls and the ground was very fast at Haydock, but if you stumble out of the stalls in a six-furlong Group One then it's game over but he did get himself back into it and he ran well, considering."