Golf-Amazing Grace wins Heritage title by two strokes

* Grace seals victory with a closing 66 * Donald has to settle for a fourth runner-up spot * Day finishes eight shots back, in tie for 23rd (Adds detail, quotes) April 17 (Reuters) - South African Branden Grace delivered a final-round master class to clinch a long expected first victory on the PGA Tour by two shots at the RBC Heritage in South Carolina on Sunday. The world number 14, who thrust himself into the limelight at the game's highest level with top-four finishes last year at the U.S. Open and PGA Championship, closed with a superb five-under-par 66 at the Harbour Town course on Hilton Head Island. Helped by pinpoint distance control with his irons and brilliant putting on lightning-fast greens, Grace mixed seven birdies with just two bogeys to post a nine-under total of 275 in the first PGA Tour event after last week's Masters. Third-round leader Luke Donald of England, striving to end a four-year title drought on the U.S. circuit, carded a 71 to share second place with Scotland's Russell Knox (67). It was Donald's fourth runner-up spot at the event. American Bryson DeChambeau (68), making his professional debut after ending his amateur career with a tie for 21st at last week's Masters, finished joint fourth at five under. Grace, who clinched his seventh European Tour victory with a successful title defence at the Qatar Masters in January, was delighted to triumph at a venue where he effectively kickstarted his PGA Tour career last year. "It put me on the map a little bit," Grace, 27, told CBS Sports about his tie for seventh at the Heritage 12 months ago. "It gave me that little push and drive to finish things up in the future. "I was really amped to get back to this place ... I like the type of golf you have to play on this place and it's worked this week." Grace began the final round three strokes off the pace and moved into a tie for the lead with Donald and Knox when he rolled in a four-footer to birdie the par-four sixth. Out in four-under 32, he tightened his grip with birdies at the 12th and 13th, sinking consecutive putts from 10 feet to forge three ahead. He did well to save par with a clutch 12-footer at the 16th, where he found sand with his first two shots, and then bogeyed the tricky par-three 17th after being bunkered off the tee before comfortably parring the last. "When I got to 12 and 13 where I made a couple of nice putts, I knew I was in there with a chance," said Grace. "That last stretch of five holes, you can't really force things. As soon as you do, it's going to backfire. You just have to stay patient and grind it, and that's what I managed to do." Australian world number one Jason Day, joint leader after 36 holes before he tumbled down the leaderboard with an error-strewn 79 in the third round, shot a 68 to tie for 23rd. (Reporting by Mark Lamport-Stokes in Los Angeles; Editing by Andrew Both)