World number one Jason Day and former Masters champion Adam Scott have fallen two shots short as Patrick Reed claimed the opening US PGA Tour Playoff event in Farmingdale, New York.

Day shot a 2-under-69 and Scott could only manage an even par round of 71 as the pair finished at 7-under in a tie for fourth at the Bethpage Black course.

Reed, who started the final round one behind Rickie Fowler, was able to put together a round of 70 to finish at 9-under, one clear of Sean O'Hair (66) and Emiliano Grillo (69).

Reed claimed his fifth US Tour win and first since January 2015.

Day was left to lament another week of wayward driving off the tee, finishing last in accuracy of the 79 players who made the cut.

"I don't think there was a tee shot that I felt comfortable over to be honest," Day said.

"Every time I was standing over the ball, I couldn't feel like it was going to be a good shot. I was fighting a left shot and I was fighting a right shot.

"With everything done, stats-wise, I didn't give myself an opportunity off the tee.

"If I give myself more opportunities to the green, if I'm in the fairways, I might have had a good chance.

"Even though I did hit a lot of greens today, I didn't hit them close enough."

Day did provide one highlight in the final round, making a curling 71-foot birdie putt on the 15th to give himself a chance at a late run.

But a three-putt for bogey from a similar distance on the next hole ended his hopes.

Scott started poorly with back-to-back bogeys but found three birdies in his next seven holes to get back into contention.

But two bogeys early on the back nine had him swimming upstream.

John Senden ensured he will survive at least one more week in the playoffs with a final round 3-under-68 moving him back to even par for the tournament and a tie for 31st.

The playoffs are now down to 100 players heading to next week's second event with Day, Scott and Senden to be joined by Marc Leishman and Aaron Baddeley at TPC Boston.

AAP