Keegan Bradley went from the last man in the BMW Championship to a winner in Colorado, closing with an even-par 72 for a one-shot victory that opened up all sorts of possibilities he never imagined possible a week ago.

Bradley pulled away on Sunday from mistake-prone Adam Scott early on the back nine and delivered a clutch shot into the par-5 17th that all but sealed the seventh victory of his PGA Tour career, and the most unlikely.

He was biting his nails a week ago, needing help just to finish at No.50 in the FedEx Cup and qualify for the second post-season event. And then he managed the mile-high air, the wind and pressure to win at Castle Pines.

“It just shows why you’ve got to grind it out because you never know how fast it can switch,” Bradley said on the 18th green, where he stood alongside his father. Mark Bradley, a longtime club professional, had never seen his 38-year-old son win in person.

The victory moved Bradley to No.4 in the FedEx Cup, sending him to the Tour Championship where he will start four shots behind Scottie Scheffler in a 72-hole chase for the $US25 million ($A37 million) prize.

There’s also another cup in play. Bradley, the first Ryder Cup captain to win a PGA Tour event since Davis Love III nine years ago, moved to No.10 in the Presidents Cup standings. The top six after the BMW Championship automatically qualified, and Jim Furyk gets six captain’s picks. Bradley will surely be in the conversation after winning for the third straight year.

Scott, a runner-up at the Scottish Open last month, was tied for the lead until starting the back nine with three soft bogeys, two of them with a wedge in his hand from the fairway. The Australian birdied the closing par 5s, but lost a big chance when he overshot the 15th green from 101 yards.

He closed with a 72, moving him to 14th on the FedEx standings.

Compatriots Jason Day (33rd) and Cam Davis (36th) saw their Playoffs campaign come to an end after finishing tied-33rd and joint-fifth at Castle Rock.

Day (71) ended his weekend one over, while Davis (66) finished eight under.

Sam Burns enjoyed a Sunday-best 65 and shared second place with Scott and Swede Ludvig Aberg (71).

Bradley earned $US4 million ($A5.9 million) for his second title in the BMW Championship, also winning at Aronimink in 2018 when he was the No.52 seed in what was then a 70-man field.

Bradley and Scott joined Tommy Fleetwood (69) and Chris Kirk (69) who moved into the top 30 to qualifying for the Tour Championship. They bumped out Brian Harman, Jason Day, Davis Thompson and Denny McCarthy.

With AAP.