Japan's Hideki Matsuyama won his first US PGA Tour title in dramatic style on Monday morning (AEST), beating Kevin Na with a par at the first play-off hole at the Memorial.

Matsuyama endured a rocky back nine at Muirfield Village that included a double-bogey five at the par-three 16th.

But he birdied the 72nd hole of regulation to complete a 3-under-par 69 and join Na on 13-under 275.

South Korea-born American Na had been in the clubhouse for some two hours having completed a bogey-free 8-under 64 for 275.

Matsuyama's hopes looked dim when he hit a poor tee shot at the final hole of regulation. He broke his driver bouncing it on the ground in disappointment.

However, he knocked his approach shot to five feet for a birdie.

They returned to 18 for the play-off, and Na was in a stream off the tee.

Matsuyama was in a bunker off the tee but he drained a 10-foot putt for par to seal the victory.

The 22-year-old Asian star, who won four times on the Japan Tour last year, is in his first season on the US PGA Tour. He became the fourth Japanese player to win on the US tour.

World number one Adam Scott (R) congratulates Hideki Matsuyama after the 18th hole of regulation play. ( Getty Images: Matt Sullivan )

Australian world number one Adam Scott made a fourth-round charge to at one point sit just one stroke off the lead, but a double-bogey on the 12th and three straight bogeys on the 14th, 15th and 16th holes proved his undoing.

Scott finished at 10-under overall in a tie for fourth place alongside American Chris Kirk.

Masters champion Bubba Watson went into the final round of the tournament hosted by Jack Nicklaus with a one-shot lead.

However, he fell back with a bogey at the14th and a double-bogey seven at the par-five 15th and missed out on the playoff by one stroke.

Watson finished alone in third after an even par 72 for 276.

ABC/AFP